Well, I mostly collect Curio & Relic firearms, so most of my guns are used. Very used. As in, thousands of rounds fired at hostile folks before I was born, and in many cases, before my parents were born. My favorite rifle (a Springfield Armory M1 Garand) was made back in 1953, and I have other guns that date back to WW-II or earlier.
I buy those old guns because I'm a collector, not just to save money over new guns. Still, there's nothing at all wrong with buying a used gun as long as it's in servicable condition and it satisfies your needs and desires.
If a pistol that you're considering has had the hell shot out of it, it should be pretty obvious when you look at it at the store before committing to buy it. A reputable dealer should help you judge the gun's condition, too, particularly if you don't feel that you're experienced enough yet to catch potential problems with the gun.
I've had generally good experiences with Turner's. I like to stop by Fowler's Gun Room on Tustin Ave. in the city of Orange, too. They're close to a Turner's on the same street, and they have a really impressive stock of new and used rifles (much more than I've seen elsewhere), plus lots of pistols, optics, reloading supplies, etc. I can't think of any other good suggestions at the moment, but I'm sure that other folks will chip in.