RE: Got my CHL, now for the hard part....
A lot of people make a mistake and buy a gun that is to big to conceal and to heavy to carry. I got a Sig P232 380 ACP that holds 7+1 rounds. It is a lot lighter than the full size guns and I can carry it in an inside the pants holster and you can't even tell I am wearing it.
If it is for your truck than a 9mm, 40 S&W or a 45 ACP would be better. I personally like the double action autos better than single action for protection. I would carry my Ruger P89 9mm if I was going to leave it in my truck.
Good luck.