Are you looking for specific convention-type stuff, or more local events?
I'm in DFW, and we have lots of stuff going on all the time. The local groups are great about having something available just about every night.
If you're talking about conventions, you just missed the Texas Freethought Convention by a few weeks. The next one will be held in Houston sometime in the Fall next year.
I'm located in central Texas as well, Brownwood, about an hour south of Abilene. I prefer not to drive 2 hours for a weekly meeting, so I am aiming at more convention-like events. Sad to hear I just missed the TFC, and I will make it a point to attend next year. Are there any other upcoming, fairly large events that I need to be informed of?