Don't knock the 9mm- Atlanta PD has one-shot-dropped plenty of gangstas with the venerable Federal 9BPLE, and computer-aided bullet design has resulted in vast improvements compared to the older hollowpoints that were around when guys like my dad formed their opinions in the 1970s that the 9mm couldn't do the job. Speer Gold Dots, Winchester Ranger T, Federal HST all test well and will make a BG good and dead if you put it in the right spot. The advantage to 9mm for CCW is you can fit more rounds in the same size package compared to 40 or 45, and the ammo is cheap enough that you can afford to shoot a lot more practice. If this is your only handgun, you'll want to shoot it a lot and 45 ammo is twice as expensive as 9mm. That said, as long as you can afford to feed a 40 or 45, it's hard to argue against a bigger hole!
Glocks are a good choice, as long as you like the ergonomics. I'm a fan of Steyr pistols since they feel much better in my hand, have less perceived recoil and kick Glock's azz in the trigger department. The MA1 series in .40 and 9mm is on sale at CDNN for $349 NIB, which is a smokin deal for the quality you get. Wish they made a .45, but their marketing decisions aren't up to par with the engineers in that outfit. Plug for
www.steyrclub.com! You can also get similar prices ($350-400) on trade-in and reconditioned Glocks. Just keep your booger hook under control when unholstering so you don't get a case of "Glock leg" LOL. G23 would be a good choice in 40 (my dad carries one). Glock's subcompact .40 is the G27. The concealable (for me) Glocks in 45 are the G30 (double stack 10+1 capacity) and the G36 (single stack 6+1). I'd be comfortable carrying either of those and will probably buy one of them in the next year or two. Can't say I've shot the Springfield XD enough to have a firm opinion, but a 9mm XD felt "okay" to me, and there's no shortage of people drooling over the new XD compact .45.
1911s are great, but if this is your first pistol it might take you some time to get comfortable with carrying cocked & locked, which is the only way a 1911 should be carried. This may or may not be an issue for you, depending on how much firearms handling you've done in the past.
When it comes to CCW, it's been said many times that you can't go wrong choosing the same caliber and ammunition that's issued to your local law enforcement. Right or wrong, the type of ammo used has been brought up in court and relied upon by firearms-ignorant juries to convict shooters in self-defense scenarios. It's one less thing a prosecutor can attack you for if you use exactly what local cops use. Clearly, there are many factors to consider when choosing a CCW gun. Do your research, handle & shoot a bunch of different models and go from there. <img src="/forums/images/graemlins/kewl.gif" alt="" />