The Bluebonnet Classic web site has NPIP testers contact info on it but I haven't looked to see if it shows right now. The show is in January and during the summer often there isn't much to see. I have the info for area 3, which is houston/brenham. I've emailed the man and never got a reply. Since I'm not going to be selling hatching eggs or shipping out of state any time soon I haven't bothered much with it.
The problem in Texas is often finding out who to contact to get the real story. I've most often heard what easttxchick said above from those who do get the testing. As luck would have it, of course, none of them are in the same region as I am.
ETA: If it were as easy as looking at the Dept. of Ag. website or doing a Google search for it in our state, threads like this probably wouldn't appear for long, especially old ones brought back to life. You pretty much just have to know someone that knows in Texas. The state websites are no help whatsoever, nor is anyone whose contact info is on said websites in relation to this testing. And I'm an old hand at google/web searches, etc.