Uprev - they write the software is in Austin and can do tuning as well. Check for a tuner near you -
UpRev - Engine Management
Cobb: COBB Tuning, 1200 Placid Avenue, Plano, TX 75074 -
CobbTuning.com - Home Page
Using both of those companies can help you find where a local tuner might be, and those two software companies write some very good tuning work for our car.