The first place you should look is at a list of Georgia natives, since that's far more likely to be a local than some exotic pet that escaped or otherwise hitch hiked to your pool. After a quick look at Frogs and Toads of Georgia I'd guess it's an Eastern Narrowmouth Toad, Gastrophryne carolinensis since this seems to be the only thing that matches the spotted belly (note that the overall colour of this species can vary pretty dramatically). I just had a quick look though and I'm definitely not familiar with all of Georgia's frogs, so you might want to study your local frogs and toads more closely.

I'd also release it near where you found it. I'm guessing you don't keep frogs, so there's no chance it picked up some exotic frog diseases while in your care. If you want to take on a frog as a pet, it's best to be prepared with proper housing and food before you take it in.

edit- I've also moved this out of the Dart Frog forum and into the "General Discussion Forum & News".