I thought to make this thread for using to find spells quickly. The spells are categorised according to proficiency level.

For the rules regarding spells and usage, players must read the game rules. I have only included the key for proficiency and nature here apart from the spells.

Key Nature of Spells
O = offensive
D = defensive
N = neutral

Proficiency Levels
Level 1 spells: 1-10
Level 2 spells: 10-15
Level 3 spells: 15-25
Level 4 spells: 25-35
Level 5 spells: 35-55
Level 6 spells: 55-75
Level 7 spells: 75-95
Level 8 spells: 95-110
Level 9 spells: 110-125
Level 10 spells: 125-150


Curses
Level 1 Archeris (O) - Conjures arrows in front of the wand that can then be propelled at high speeds.

Averte Statum (O) - Knocks something off its feet and sends them flying several meters.
Level 2 Felinus Vulnus (O) - Produces the effect of claw strikes as inflicted by a cat. The spell causes great irritation to the skin and may cause a wizard to lack focus (10% chance of missing next spell)(known to Atticus Prince and Professor Forsyth).

Serpensortia (N) -Conjures a snake from the wand.

Vipera Evanesca (D) - Counter Spell for Serpensortia. Seems not to merely "Vanish", but causes the snake to smoulder from head and tail until it is reduced to a pile of ashes.

Babbling Curse (Blatero) (O) - Makes the victim unable to articulate words.
Level 3 Arania Exumai (O) - The Spider-killing Curse is a spell used to kill or, at least, supposed to.

Furnunculus (D) - Causes the target to become covered in boils.

Impedimenta (D) - This powerful spell is capable of tripping, freezing, binding, knocking back and generally impeding the target's progress towards the caster.
Level 4 Petrificus Totalus (D) - Used to temporarily bind the victim's body in a position much like that of a soldier at attention; this spell does not restrict breathing or seeing, and the victim will usually fall to the ground.

Incendio (O) - Produces fire shooting out of the wand.
Level 5 Confringo (O) - Causes anything that the spell meets to explode in flames.

Conjunctivis Curse (O) - A curse that causes great pain to the victim's eyes.

Reducto (O) - Enables the caster to explode solid objects.

Locomotor Mortis (O) - Locks the legs together, preventing the victim from moving the legs in any fashion. The target can hop when affected by this curse, but walking is impossible without the countercurse.

Destructum (O) - Destroys shield hexes and charms.

Mobilicorpus (N) - Lifts a body a few inches off the ground and levitates it where the caster points his or her wand.

Morsmodre (N) - Produces the Dark Mark.
Level 6 Expulso (O) - A spell that causes an object to explode. The force of the explosion may depend on the intent of the caster.

Axelo (O) - Causes severe internal injury.

Langlock (D) - Glues the victim's tongue to the roof of his/her mouth. Created by Severus Snape.

Muffliato (D) - Keeps nearby people, or those to whom the wand is directed, from hearing nearby conversations.
Level 7 Sectumsempra (O) - Violently wounds the target; described as being as though the subject had been "slashed by a sword".

Flagrante Curse (D) - Causes any object affected to burn human skin when touched.
Level 8 Levicorpus (O) - The victim is dangled upside-down by one of his/her ankles, sometimes accompanied by a flash of white light.

Liberacorpus (D) - The countercurse of Levicorpus.
Level 9 Geminio (N) - Creates a duplicate of any object upon which it is cast.
Level 10 Unbreakable Vow (N) - Causes a vow taken by a witch or wizard to be inviolable; if he or she should break it, the consequence is death. It manifests itself as interlinking chains of fire binding the clasped hands of the people taking the Vow; the fire shoots out as a tongue of flame from the wand of the Binder (a witness to the Vow) every time the person who takes the vow makes a promise. The flames then form into the linking chains. According to Ron Weasely, the spell causes death to anyone who breaks the vow.

Fiendfyre Curse (O) - Dangerous, uncontrollable and extremely powerful fire which can take the form of beasts (all area spell, 30% chance of damage to caster).

Charms
Level 1 Riddikulus (N) - A spell used when fighting a Boggart, "Riddikulus" forces the Boggart to take the appearance of an object the caster is focusing on. Best results can be achieved if the caster is focusing on something humorous, with the desire that laughter will weaken the Boggart.

Fera Verto (N) - Transfigures an animal into a goblet.

Scourgify (N) - Used to clean something.

Wingardium Leviosa (N) - Levitates objects.

Lumos (N) - Produces a light on the end of the wand.

Nox (N) - Countercharm to Lumos.
Level 2 Orchideous (N) - Makes a bouquet of flowers appear out of the caster's wand.

Anapneo (N) - clears the airway.

Aguamenti (N) - Produces a jet of water from the tip of a wand.

Reparo (N) - Used to repair broken or damaged objects.

Hover Charm (N) - An object is levitated off the ground and moved according to the caster.

Ferula (N) - Creates a bandage and a splint.
Level 3 Incarnum Inflamarae (N) - sends a ball of fire from the wand.

Reparifors (D) - Heals minor magical injuries.

Episkey (D) - Used to heal relatively minor injuries. When this spell is cast, the person feels his/her injured body part go very hot and then very cold.

Banishing Charm (N) - Propels an object away from the caster.

Engorgio (N) - Causes objects to swell in size.

Colloshoo (D) - Glues the victim's shoes to the ground.
Level 4 Baubilleous (N) - Creates a bright bolt of white light from the tip of the wand.

Carpe Retractum (N) - Produces a magical rope attached to the caster's wand that pulls objects towards the spell caster.

Rennevarte (N) - Brings someone out of unconsciousness.

Sonorus (N) - Magnifies the spell caster’s voice, functioning as a magical.

Diffindo (N) - Rips objects.

Freezing Charm (N) - Causes an object to freeze.

Silencio (N) - Silences something immediately.
Level 5 Vulnera Sanentur (D) - Causes wounds and gashes to heal up and any blood to return to the victim.

Aqua Eructo (O) - Aqua Eructo is a spell used to create a jet of clear water, and then control it.

Protego (D) - The Shield Charmcauses minor to strong jinxes, curses, and hexes to rebound upon the attacker, or at least prevents them from having their full effect. It can also cause a shield to erupt from the caster's wand (All area affect).

Impervius Charm (Impervius, D) - This spell makes something repel (literally, become impervious to) substances and outside forces, including water.

Expecto Patronum (D) - Conjures a Patronus. A patronus is commonly used to dispel dementors, but can also be used to communicate messages.

Confundus Charm (Confundo O) - Causes the victim to become confused, befuddled, overly forgetful and prone to follow simple orders without thinking about them.

Aresto Momentum (N) -Slows the movement of multiple objects, including the caster if so desired.

Expelliarmus (D) - This spell is used to disarm another wizard, typically by causing the victim's wand to fly out of reach.

Repello Mugletum (D) - Repels Muggles (All area affect).

Calloportus (D) - Locks doors, making them unable to be opened.

Aparecium (D) - Makes invisible ink visible.
Level 6 Ossio Dispersimus (N) - Removes bones.

Obliviate (N) - Used to hide a memory of a particular event.

Fianto Duri (D, Di: 6) - Creates an impassable shield between the caster and the enemy.

Summoning Charm (Accio) (N) - This charm summons an object to the caster, potentially over a significant distance. It can be used in two ways: by casting the charm, and then naming the object desired, or by pointing the wand at the desired object during or immediately following the incantation to "pull" it toward the user.
Level 7 Protego Horribilis (D) - Provides some form of protection against Dark Magic. (All area affect)

Protego Totalum (D) - Provides protection of some form for an area or dwelling. (All area affect)

Disillusionment Charm (N)- Causes the target to become invisible, or close to it.

Cave Inimicum (D) - Spell used to strengthen an enclosure against enemies (All area affect),
Level 8 Portus (N) - Makes an item a portkey

Homorphus Charm (D) - Causes animagi or transfigured objects to revert to their original form

Caterwauling Charm (D) - Anyone entering the perimeter of a Caterwauling Charm sets off a high-pitched shriek. (All area affect)

Homenum Revelio (D) - Reveals humans near the caster. (All area affect)
Level 9 Fidelius Charm (D) - A charm involving secret information hidden within the soul of a Secret-Keeper. This information is irretrievable until the Secret-Keeper chooses to reveal it; those who have the secret revealed to them cannot reveal it to others.
Level 10 Finite Incantatem (N) - Negates many spells or the effects of many spells.

Hexes
Level 1 Rictusempra (N) - The subject experiences the sensation of being tickled.

Vera Verto (N) - Used to turn an animal into a water goblet.

Flipendo (N) - A jinx that knocks enemies back, causing them to flip over.

Alerto Ascendare(N) - Shoots an object or creature into the air.

Alohamora (O) - Used to unlock doors, but doors can be bewitched so this spell has no effect.

Scribblifors (N) - Used to turn objects into quills.

Denutio (N) - Used to conjure the mark of the Society of Dantalion (Known to Atticus, Nigel, Lance and Geoffrey).
Level 2 Snufflifors (N) - Used to turn books into mice.

Avifors (N) - Used to turn a small statue into a bird.

Avis (N) - conjures birds from the wand tip.

Opugno (O) - When used in conjunction with the Avis hex, causes the birds to attack a target.

Immobulus (D) - Renders the target immobile for a short period of time.

Descendo (N) - Makes things sink.

Match to Needle Hex (N) - Turns a match into a needle.
Level 3 Locomotor (N) - The spell causes the named object to rise in the air and move around at the will of the caster.

Glisseo (N) - Used to make objects slippery.

Melofors (N) - Used to turn an opponent's head into a pumpkin/
Level 4 Ducklifors (D) Used to turn an opponent into a duck.

Stinging Hex (O) - Causes the victim to feel the sensation of being stung.

Relashio (D) - Used to force someone or something to release that which it holds or grapples by means of shooting fiery sparks out or, underwater, shooting hot bursts of water.

Trip Hex (O) - Causes the victim of the hex to trip and fall.

Tarantellego (O) - Makes victim's legs dance uncontrollably, so the victim cannot control his or her movement.

Stupefy (O) - Stuns a victim.
Level 5 Incarcifors (O) Used to transfigure an object to capture an opponent.

Aparecium (D) - Makes invisible ink visible.

Evanecso (N) - Makes the target vanish.

Obscuro (D) - Causes a blindfold to appear over the victim's eyes, obstructing his/her view of his/her surroundings.

Defodio (O) - This spell causes deep gouges to appear in the object targeted by the spell.

Deprimo (N) - This spell places immense downward pressure upon its target, which may result in the violent fracturing of said target.

Prior Incantatem (N) - Causes the echo (a shadow or image) of the last spell cast by a wand to emanate from it.

Bombardia (O) - Causes a small explosion.

Duro (N) - Used to turn objects to stone.

Lapifors (N) - Used to turn a small object or creature into a rabbit.

Reparifarge (D) - Reverses unsuccessful transfigurations.
Level 6 Deletrius (D) - Removes evidence of previous spells cast by the wand, revealed by Prior Incantato.

Incarcerous (D) - Ties someone or something up with ropes.
Level 7 Pullus (D) - Used to turn opponents into geese.

Steelclaw Hex (O) - Used to make an animal's claws bigger and made of steel.

Tentaclifors (O) - Used to turn a person's head into a tentacle.
Level 8 Salvio Hexia (D) - Provides some form of protection against hexes.

Bombarda Maxima(O) - Causes a large explosion.

Specialis Revelio (N) - Causes an object to show its hidden secrets or magical properties.
Level 9 Draconifors (O) - Used to turn a dragon statue into a real dragon that will breathe fire.
Level 10 Ebublio (O) - Used to make the victim inflate and then explode into hundreds of water bubbles.

Hurling Hex (O) - Causes brooms to vibrate violently in the air and try to buck their rider off.

Taboo (O) - A hex which may be placed upon a word or a name, so that whenever that word is spoken, a magical disturbance is created that alerts the caster of the Taboo to the location of the speaker. Any protective enchantments in effect around the speaker are broken when the Tabooed word is spoken aloud. (All are affect)

Piertotem Locomotor (O) - Spell used to animate statues and suits of armour to do the caster's bidding.

Anti-Apparition/Disapparation Jinx (D) - Makes apparation or disapparation impossible. (All area affect)

Unforgivable Curses These curses are illegal. If anyone were to use them, the Ministry could prosecute them and send them to Azkaban for a length of time.

Imperius Curse (Imperio, O, Di: 10) - A curse used to invade the mind of the victim, putting them at the mercy of the caster

Cruciatus Curse (Crucio, O, Di: 10) - The torture curse, used to inflict extreme amounts of pain upon the victim. If tortured enough in a short period of time, the victim could be rendered insane.

The Killing Curse (Avada Kedavra, O, Di:10) - Kills the victim

A note on Dark Magic: Dark Magic may cause some wounds that are harder to heal with basic potions or magic.

A note on Unforgivable Curses: These curses can only be utilized by highly skillful wizards. These curses are empowered by the emotions and intent of the Wizard or Witch casting them; thus you must have the intent in torturing someone just for the enjoyment in order to use Crucio's full potential. The same goes for Avada Kedavra; you must have the intent to kill for the enjoyment of killing or with a heart set on killing someone out of pure revenge. No righteous sense of justice may be able to use these Curses without them being under-powered or backfire. Thus a mere student cannot truly use the full potential of any Curse unless they are highly skilled and/or have the pure intent of killing/torturing/controlling someone without any remorse. It is illegal to use unforgivable curses on humans.

Another note on Unforgivable Curses: At this point, Aurors are the only legal users for these three curses due to their task in hunting down the last of the Death Eaters. Outside of that class, anyone who uses it; both Dark and Good Wizard, will be immediately sent to Azkaban after a quick trial. It is impossible to escape or be innocent in the case of using an Unforgivable Curse; whether it succeeds or not. It is known that the Ministry may pardon an unauthorized user in the Unforgivable Curses, but it is very rare.