Dr. Mark Drela @ MIT is a great resource for these things. He is also an RC Sailplane enthusiast, so that is where I know him from. He is one of the most knowledgeable, helpful guys around, and makes all of his airfoils available to the public.

http://raphael.mit.edu/DRELA.bio.html
http://ww w.monkeytumble.com/dnc/supergee.htm