First thing you need to do is make up your mind not to rush. There are a lot of really great 9mm handguns out there. You don't need to fire it to find out if it fits your hand and will conceal the way you want it to. Do you want it for range shooting or defense - be honest.
Can you get a carry permit in your area easily? Do you need a permit just to buy, like in NY? Do you want it to have a large capacity.
I have 2 carry weapons - one is a Kahr P9 and the other is a small S&W Airweight revolver. No great capacity in either one, but they hide easily and both shoot very well. So it's a very personal decission.