I've carried nothing but a full size 1911 for years. The hard part of concealing a handgun is the width and the grip frame length. The 1911 is thinner than most and no longer in the grip frame than any other decently sized handgun. I did try to carry a Kel-Tek P3AT as a BUG for a while, but actually found it much more uncomfortable, it kept poking me in the side.
Step one is to make the decision to carry a decent sized pistol. Accept that you won't be able to pocket carry, most "tuckable" holsters will make you look like a cossack dancer and people who carry mouseguns will tell you you're needlessly torturing yourself. Remember what you're gaining. A larger pistol that is easier to operate, has a longer sight radius, less recoil, chambered in something far larger than .32 or .380 and you happen to shoot it well. If you haven't made up your mind to really do it, you'll wind up leaving it at home. It can be a pain in the tuckus until you get it worked out for yourself. Decide to do it and persevere. It will become second nature.
Step two is a good gunbelt. A nice, thick leather belt isn't necesarily a gunbelt. A gunbelt is purpose made and will cost you anywhere between forty bucks for a Wilderness (my personal favorite, regardless of cost) to hundreds if you go in for custom work with all the fancy engraving and exotic materials. A good holster is worthless is held up by a crappy belt.
Step three is the holster. Decide if you want to go IWB or OWB. I find IWB gives me a bit more leeway in clothing, but OWB is a bit more comfortable. I carry OWB when I can, IWB when I need to. Expect to buy more than one holster. Expect to buy more than three or four holsters. Every maker has certain angles and features that differentiate them from everyone else. It will take some experimenting. You don't have to go broke, though. Research your first purchase as well as you can, then compare your experience to what else is available. Make due with the first while you save and research the next. And so on. One day, you'll find "it". And it will be different than my "it" because we are shaped differently, move differently and have different levels of required retention and concealment. We also probably have differing levels of acceptance for discomfort or inconvenience. All these figure into holster choice. Off the rack, Galco and El Paso Saddlery make good stuff. If you are willing to wait a bit, there are custom makers that will provide leather just as good, in a lot of cases better, for the same money. Custom stuff I like includes the Crossbreed Supertuck, Sparks Versa-Max, Sparks Summer Special, Bromeland Max-Con (I think he's out of business, though) and one whose name escapes me. I can't go look, my wife's asleep in the bedroom. Waking her up looking at holsters is a recipe for disaster. I personally don't like shoulder holsters and can't tell you a thing about them. Some people like them, though. You may wind up being one of those unfortunate souls, ahem, I mean lucky individuals.
Step four is magazines. If you carry ANY type of autoloader, you need at least one reload. Tossing lead downrange has nothing to do with it. The most common source of malfunctions in an autoloading pistol is magazine failure. I find that especially carrying OWB, two reloads simply balances out the weight better. IWB it doesn't seem to matter as much since the waistband of my pants, as well as the belt, are supporting the pistol. If you go this route, remember that two single carriers take up less real estate on the belt than a double carrier. Unless they're paddle style. Then they are massive space hogs.
Step five is to realize that ninety nine percent of the people around you are positively clueless. One percent will spot a little lump in your clothing, and ninety nine percent of those will assume it's a cell phone, blackberry, etc. When in doubt, do the mirror or spouse check. If I question the "hang" of a certain shirt or jacket, I simply ask my wife. Sometimes I ask her when I'm not carrying, just to keep her honest!