Audio Xpert on Charleston is pretty much the best vintage/used store in town; Bobby...the guy who runs it....is an authorized McIntosh service center, so he knows his stuff. The store's not much to look at - it's in an older part of town in a "well-worn" strip mall, but it's stuffed with gear, including some good finds.
As far as high-end shops, I've been dealing with Premiere Home Entertainment for 12 years. Unfortunately, it's no longer a walk-in store; it's by appointment only, because the bulk of their business is now high-end AV installs and other work; Premiere carries some good lines; their customer service is good.
It's disappointing though that in a city of 2 million people, there aren't more stand-alone high-end shops. You would think that in a city full of musicians and entertainers, you'd have that, but unfortunately you don't.
But it's not a wasteland. I'm in the process of building a good system and can get anything I need.
Jeff