Have you checked with Hoke Nunan from the TSDMGK in Cedar Park? Maybe he has an idea as he is around teh corner. (if there is "around the corner" in a big state like Texas )
I've asked around a bit and done a bunch of Googling wth no luck. However, Texas Tech is located in Lubbock, and it's quite a large university -- I'd bet there are at least some Tang Soo Do clubs that meet on campus. Perhaps the office of student activities might have some info on martial arts clubs in the area?