Chris - If you really are going to buy only one gun this year and it's going to be a 9mm, I would suggest you go to the gun show and pick up several to see how they feel in your hands. Find 2-4 that you really like and them go to a local range that rents guns and try them out.
It may cost you $100 or so to evaluate these guns at the range, but I think it is a great investment if you really plan on holding onto a gun. There are so many great 9mms out there and they can feel so very different when handling an shooting them.
Try not to get caught up in the emotion of buying the gun - there are many slick sales guys who will come up with all sorts of crap on why their gun is the best gun for you. If you can - take a few days to sleep on your decision and evaluate some other guns for comparison.
People have already mantioned several good guns here. Some basics you might want to think about:
Is this gun for primarily for concealed carry, glove box or range/plinking?
This question helps determine the size of the gun.
Do you want Polymer or metal?
If metal - aluminum or steel?
If Steel - stainless?
(they get heavy for long carry)
Do you want a gun with a safety?
Traditional Double Action, some type of Glock/safe/whatever they call it action, or Single Action?
Where do you like your mag release, safety and slide release to be?
I don't really expect you to have answers for all these questions, but as you look over the different guns at the show, they are something to think about.
I've been on a 3rd Gen S&W kick, but I do have a Browning Hi-Power, Glock 19 & 17, Walther P88 & P99, CZ85, H&K USP, Kahr, Sig 220 (.45), and some othwers.
Why the S&W 3rd Generation guns? - no concealed carry in my state so it's mostly range time for me, and at the range I like all stainless steel, traditional double action guns with a safety that I can put 100,000 rounds through and still pas on to my grandchildren. A S&W 5906TSW is all that, have been on the used market for reasonable prices, and I shoot them well.
Or you can just do like many of us - buy a gun, shoot it, handle it, figure out if you really like it or not. Sell or trade it in for something else. Repeat. Repeat. Repeat. Go back to one of the guns you previously owned. Etc. Etc.
You may wind up doing this anyway...