There is no regulating authority in Texas. The TRCC is dead ... (thank goodness) You may have county or city code and/or inspections to deal with though.
General and home improvement contractors do not need to be registered in Texas, for jobs under $10,000. For residential remodels over $10,000 you must register with the trcc. Ofcourse commercial remodel/repair jobs do not fall under trcc guidelines and can be done with no license or state registration. Homebuilders are required to register with the state. A search for registered builders is provided on the Texas Residential Construction Commission website. Also - I believe the end of Aug '09 marks the end of the trcc and these regulations. It really depends on where you are working. Some cities require a bond as well. El Paso requires a city bond. Some other big cities do as well.