First off, be aware going into it that your first carry setup will likely be be an experiment. In other words, most of use go through several handguns and/or carry systems before we find the sweet spot. In that regard, if you can buy a quality used
firearm and save a little up front, if it doesn't work out you can always sell it for about what you paid for it.
Also, getting some training up front before you buy anything is great advice. As another poster said, buy a revolver because you are inexperienced is not the right reason to buy one. This is where the experimentation comes in I described above. If you have a friend that will let you try different guns, that would be ideal. Renting is fine too, but it can get expensive.
As for snub nose revolvers like the ubiquitous S&W J Frame, many say they are an expert's gun, due to their tiny grips, almost non-existant sights and puny sight radius. The same can be said for ultra compact autos too though. Though for most
people they are a challenge to shoot, some people I know don't have any such troubles with them. My sister's carry gun is a S&W .38 Bodyguard, and without the aid of the laser she has no problems putting all 5 shots into a 2" group at 7 yards (slow fire), or onto a pie plate at the same distance rapid fire. She's a better shot than I with a snub, but I do alright as well. Same for my father. Then again, my wife can't hit a 11 x 14" target at 7 yards with my S&W 642 (she did hit the ceiling at the indoor range though
). So yes, try before buy if at all possible.
Actually, I don't carry my 642 all that often these days. Because with high quality gear (holster and gun belt) and the right attire (and with the assumption that you don't have any significant back problems), carrying larger guns isn't all that difficult. Sure, it takes some getting used to. I wore my 5" 1911 around the house for about a week before it became fairly comfortable. Today when I carry it, I hardly notice it at all. My favorite all around carry gun is a 4" S&W Model 19, and in a horsehide Lobo Gunleather IWB holster, and it is barely more noticeable than the thinner 1911.
Going back to carry gear (holster and belt), those items increase in importance as gun size and particularly weight increase. For example, web's P32 pictured above would work fine in a cheapie nylon holster attached to a $10 wal-mart belt. Such a combo however would not be rigid or stable enough to support a 4" S&W N Frame, which requires a true gun belt and a high end leather or kydex holster. Medium sized guns, like a Kahr 9mm or Ruger SP101, are usually fine with an entry level leather holster and good thick belt (not necessarily a gun belt).
Finally, tom is correct about budgeting for the true costs (training, gear, ammo, gun, possible new clothing to dress around the gun of your choosing, etc). One aspect to consider in favor of a revolver (not that this should be the only deciding factor) is the general lack and expense of ammo at the present time. For me personally, I don't require a revolver to fire nearly as much practice and carry ammo before I trust it for carry duty. Before I carried my 1911, I fed it 500 rounds of cheapie stuff and something like 150 to 200 rounds of expensive hollow points before I trusted it. Given the current ammo shortage, I'm not sure that I could fine 200 rounds of hollow points to test ... not to mention afford it in my present situation.