In the realm of semi-auto pistols, the ultimate concealed carry with reasonable power would probably fall to the Kel-Tec P3AT (.380). This little gun can literally go anywhere.
For 9mm or larger, I gotta agree on the Kahr, but Kel-Tec has a new 9mm coming out as well.
For wheelguns, the S&W airweight body guard is hard to beat. Charter Arms and Taurus both have similar revolvers, but under certain circumstances the revolver is not easy to conceal comfortably (for some people).
Typical dress for a guy in Florida during the April through October time-frame is usually shorts and t-shirt, or kahki pants and a polo/golf shirt. If your shirt is not tucked in, you will be able to carry a larger weapon. If, however, you choose to tuck your shirt in, and depending on your body size/shape, you may be limited to pocket carry. The last thing you really want in your pocket is nearly two pounds of iron and lead. That's why the Kel-Tec .380 is such a nice piece to carry. If you are able to carry inside the waistband and are comfortable with all day carry (sitting, driving, walking, SWEATING!) then your options for a larger weapon would probably include all the usuual Glock, Sig, 1911s and such.
Sure, that Para 14-45 1911 looks like a great pistol, but try carrying it on your body all day long when the temps are pushing 100 and the humidity is 99% and you are golfing, or your wife is dragging your ass around a flea market. You'll be glad that Glock, Springfield, Taurus, Kel-Tec and others have light weight, easy to conceal weapons to choose from.