This is the place to start if you want to learn what's available in each set, and what's good and bad about them (in my opinion, of course. Yours will vary, I guarantee it :)
Get the big picture - the overview of all the sets, including cheesy statistics and graphs
The Collector's FAQ - Most of the information that's on these pages, gathered in one convenient downloadable PDF document. I update these pages much more often than the downloadable file so use the links below for the most current information.
See the details of the individual sets - including breakdown by faction and rarity, plus obligatory cheesy statistics. These links open in new windows. I need to add pages for the new Inner Kingdom Games sets, and there are some pieces missing that I'll have to go back to fill in later.
Limited / Standard
Year of the Dragon
Netherworld 2: Back Through The Portals (most folks just call it Netherworld 2)
Boom Chaka Laka
Can of Whupass, Old Skool Edition
Seven Masters vs. The Underworld (most folks just call it Seven Masters)
Two-Fisted Tales of the Secret War (a lot of people call it the "Pulp" set)
Shurikens and Six Guns
Empire of Evil
Combat in Kowloon
Back for Seconds
Reloaded (printing expected early in 2013)
The Shadowfist Players' Guide, Volume 1 (from Daedalus)
Shadowfist stuff that isn't cards (T-shirts, posters, etc.)
Magazine articles - a comprehensive (well, maybe someday :) list of Shadowfist articles, and the entire article where I've been able to get permission.
Printer's errors and such - weird stamps, miscuts, things that you were not meant to see.