There's actually the North American Reptile Breeders Conference coming up soon in Tinley Park on March 17-18! I went last fall and, while most of it was reptiles, some vendors were selling various kinds of frogs. Just be careful to check them out, ask for sources, diets, etc. Saw someone trying to sell a poor baby pacman with jaw disfigurement due to MBD.

Entrance fee is $15. Here's the site for more info: http://www.narbc.com/