The primary store in Birmingham is Reef Life right off of 280. Depending on when you go, they have an okay coral selection. They almost always have a good selection of fish though, and I usually feel safe buying fish from them. The other store in town is Aquarium Imports off of US31. They're alright, probably worth stopping by if you already drove 100 miles.
I really like going to shows, so here's a list of events in the area:
Montgomery had a big show this year called the CODAX Expo. The main guy is part of Glow Pop, and it was definitely the largest show I've been to in this state.
Atlanta has a show once or twice a year, I haven't been but I know people make the trip over from Birmingham.
Birmingham usually has 2 small shows, but I think they've been getting smaller over the years.
Huntsville has a couple of smaller shows put on my R2R members.
Nashville has the MTRC expo which I've heard is pretty big. There's also always Reefapalooza in Orlando.