Georgia is full of jon boat clubs... Check out GON.com too if you're not familiar with it.
High Voltage Bass Anglers is one, and they fish lakes like Varner, Horton, Black Shoals... but I don't think that's middle GA. I know there is some down there, but for the life of me I can't remember what they are. Put a post out on GON and you'll get the answers you're looking for.