I have been there a few times, but to tell the truth, I don't know my way around by memory.
Parasol bar is in the Hyatt straight back from the peachtree st. entrance (parade comes down peachtree). It is pretty much standing room only. Not sure about the others. Have a feeling they are the same.
I guess we might want to locate it more central. Or maybe off the beaten path to make it easy to locate one another.
Edit: Oh, there is a life size Jabba the Hut in one of the hotels.