There are a few.
John Fort Audio. He is probably the nicest and most knowledgeable guy in D/FW. He carries Vandersteen, Gallo and some horns.
High End Audio. Vu is a nice guy but, don't expect any kind of discount. B&W and Martin Logan.
Audio Concepts. They carry Proac, Wilson, Paradigm, Linn and Rega. Get ready for the stuck up/snooty audio dealer experience. Although there is one sales person there that is down to earth. Sorry I can't remember his name.
Crystal Clear. Don is ok but, just know that what he carries is the best and everything else doesn't compare.