If there is a gun show nearby you should go to it. That way you can handle basically any gun made. Before you go get some ideas going though on what caliber, brand and size. By far the easiest to work guns out there are Glocks. I'm sure anybody who has over 4-5 handguns has a Glock. I think this is the way for you to go. Glock makes a full-size, compact, and subcompact model in every caliber(.45,9mm,.40,.357sig, and 10mm). They basically have any type of semi-auto handgun in their lineup.
Another thing, how big are you? height,weight Some people can conceal a Desert Eagle comfortably and others can only conceal a Kel-Tec P32.
Edited to add: The Springfield XD which is mentioned above is a good choice but they are limited in caliber and size. Only available in a 4" model in 9mm or .40 s&w, unless you go to the sub-compact ones which I think are too small for any type of shooting.