It's about 2 hours away, but the State Farmers Market in Raleigh has a couple dealers. One is located under a tent in the parking lot and he has a good variety - sedums, cacti, living stones, and other drought tolerant plants like desert rose. There are more succulents inside with the rest of the plants/produce as well. You should check it out if you have the time, it's a nice little trip.

And I bet you can't wait to drive 2 more hours on that boring I-40! Are you looking for greenhouses or just succents? Do you already have a source for the greenhouses there? Maybe calling some of the florist there could lead you to succulent sources. What do you have to lose by some phone calls? It's the South, they are friendly.