I have found a couple at Wally World. I think that is where I got my Shooter's Bibles. You may also try B. Dalton or other big bookstore chain. Academy has some books also. As far as Houston goes, I can't really be of more help than that.
I'm going to grab the Blue Book there, but i wanted to be able to thumb through the others before i bought them so that i would know if it was what i was looking for and not a narrative history book or another picture book with very little info. I need to increase my library because I'm about to start offering appraisals.
You can also try a Barnes and Noble the might have what you are looking for .
Last year I found The Ultimate Guide to U.S. Army Survival Skills,Tactics and Techniques there , 954 pages
of good info for 14.95, it was quite a read.
The book man that comes to most all the local gun shows has a good variety. Don't know if he will be at Pasadena next weekend, but I am pretty sure he will be at the GRB the following weekend.
Next, check Collectors Firearms they have an outstanding firearms book collection.