A lot of great JC programs in Texas, also in Louisiana and Oklahoma. Some of the most well known are Navarro, Grayson, San Jacinto and Howard. But there are plenty of more that do a great job of moving players on to D1 programs...Angelina, North Central, Northeast, Bossier Parish, Midland...just to name a few. For example, if I am not mistaken, two of the starters on last year's Mississippi State College World Series team were alumni of the Panola College Ponies. Most of the school websites have a section for athletics and you can find where the baseball program has sent former players.
I would say that if your son can hit, he will get an opportunity to play. From my observations, most JUCO teams always run short on hitters. Especially with the new bats. Make sure your son understands what he is signing up for before committing. Junior Colleges are normally "bare bones" operations and a lot of responsibility is placed on the player both athletically and academically. Most of the facilities are nice but do not compare to a big D1 program. Additionally, while your son's former high school classmates are going to football games and living it up next fall, his social opportunities will not be as robust.
That said, if your son is looking for an opportunity to advance his baseball career and can take care of his business, I am a firm believer in JUCO baseball in Texas and the surrounding states. Look at the rosters of the baseball teams in the Big 12, SEC, Conference USA, Southland Conference, etc. and you will normally find a good amount of former junior college players listed.
Good luck!