I buy the majority of my livestock from Aquarium Imports in Hoover, and I have had nothing but good experiences with them.
The store may not look like much (they've been in the same location without a remodel since the '70s), but their livestock is very healthy, and all 3 guys that work there are very knowledgeable and helpful.
I've bought some coral from Aquarium Designs, and it has done very well. they have a larger selection of corals, but I see lots of dead fish in their tanks every time I go in there.