We were going to Atlanta for non-bonsai reasons. I googled bonsai Atlanta and found a couple of references, and we decided to take a short trip to Conyers, about half an hour drive away, and found Bonsai by the Monastery, a side business by a Trappist monastery. They have a very nice set of trees in the garden, a lot of trees for sale in the $1,000-$2,000 range, a lot of untrained material in the $40 range, and what they say is the biggest collection of pots in the US. They also had a lot of tools, akadama, etc. I was there to get pots and they had far more than I needed.
They don't do mail order do visiting is the only option. They are 3 hours from our house but 30 minutes from grandchild #2. Probably not worth a trip by itself, but a good side trip.