Below is a collection of strategy guides for Stainless Steel, both overall and for specific factions. Some are for the RR/RC compilation but the basics for each faction in the compilation are still the same as SS so they are still useful reading.
Thanks to the authors of all contributors (+rep 'em when you can)
Title: Stainless Steel Standards: Campaign Bible
Author: Mega Tortas
Link: http://www.twcenter.net/forums/showthread.php?t=329518
Title: A Guide to the Russians (Novgorod and Kievan Rus)
Author: Meese
Link: http://www.twcenter.net/forums/showthread.php?t=331248
Title: A guide to Lithuania (RR/RC)
Author: JorisOfHolland
Link: http://www.twcenter.net/forums/showthread.php?t=331632
Title: Faction Guide: Denmark
Author: PerXX
Link: http://www.twcenter.net/forums/showthread.php?t=333044
Title: Poland: Late Era Stainless Steel Guidebook
Author: Silhouette
Link: http://www.twcenter.net/forums/showthread.php?t=333727
Title: Liberal Teutonic Order Guide (6.2 "vanilla" on VH/VH)
Author: KittySN
Link: http://www.twcenter.net/forums/showthread.php?t=309438
Title: A guide to the Crown of Aragon SS 6.2
Author: Triobios
Link: http://www.twcenter.net/forums/showthread.php?t=337949
Title:Sir Walter's fantastic invaluable strategic and military tips
Author: Sir Walter
Link: http://www.twcenter.net/forums/showthread.php?t=342991
Not SS specific, but this is a good guide to guilds: http://www.twcenter.net/forums/showthread.php?t=77577
If any guides pop up that people think should be in here, feel free to PM me