Hi, I've been living in Houston for 8 years now and like it here. It's still one of the more affordable cities in the U.S. My rent is about a third of what my friend pays in New Jersey across from Manhattan.
There are plenty of gun stores around, though I find their prices generally on the high side. Carter's country (4 locations around Houston) has a good selection with many guns on sale and a good choice of used guns as well. As has been mentioned, there are frequent gun shows here, and I've found some excellent deals at them. The best shows tend to be at the George R. Brown convention center and Reliant center. The show in Pasadena is better than the one up in Humble, which is very small. This from a gun show junky.
There are many nice places to live around town. I live close to the galleria and have never had any trouble walking around at night (I CCW, though). The good suburbs are Sugar Land, the Woodlands and Bellaire. Good advice on living close to work, as the traffic has got much worse since I've moved down here (especially around the galleria area). From what I understand, the commute from Sugar Land is not as bad as, say, Katy. I-10 seems always backed up. Generally speaking, avoid living anywhere east of downtown and places like Pasadena.