Perhaps get ahold of Keith Warren over on YouTube. He hunts with air guns in Texas quite often and may know someone that can help you.
Have you looked online for gun clubs in your area? Many time gun enthusiasts don't limit themselves to just firearms or just air guns. But, will enjoy all the various disciplines. (especially in the Lone Star State).
Also, you should be able to buy a Gamo air rifle at Bass Pro, Big5, Walmart, or others for a couple of bucks. If you get one with Whisper Fusion your neighbors will probably never hear it. Stay away from magnum and Mach1 models as they can more easily fire pellets faster than the speed of sound and that "crack" cannot be suppressed! I'd recommend a Swarm model in .22 to get the 10-shot repeater ability and I'd shoot Predator Polymag ammo to cut down on pass-troughs.
Good luck,
~ Mondo