It's always a good idea to check the appropriate state boards for info like this. About halfway down the first page of the Texas discussion board, there's a thread that lists a bunch of good headshop-related info:
http://boards.cannabis.com/showthread.php?t=67074
birdgirl73 Reviewed by birdgirl73 on . Dallas, TX Headshop Locations anyone know of any dallas headshops? Rating: 5