http://www.thevalkyrie.com/ladybumps/stories/index.htm is a place I don't hear talked about too often. I think they're part of the BEA but I can't remember and you don't see links to it from the BEA site anymore.
It's got some good free stories on there, though some might be a little old. It's got like...all of the st cats stories ever written, I think.
Edit: Woops, sorry just saw that someone else posted this earlier.