Here are some mini tutorials (painting) with brushes which are useful for skinning.
Greetings A.U.
http://www.imaginefx.com/02287754331...vironment.html
http://www.imaginefx.com/02287754333...d-costume.html
http://www.imaginefx.com/02287754332...-and-hair.html
http://www.imaginefx.com/02287754333...rush-tips.html
http://www.imaginefx.com/02287754330...photoshop.html