One very important thing that most of the time is overlooked is if you moved during any time of the year you must make sure you have updated your address with your employer. This is specially necessary if you relocated to a different state or no longer work at the same place. Otherwise your W2 may be lost in the mail.
I have heard of people who wait until the last minute to file because they are waiting for their W2 from their previous employer. When they do not receive it they either file with out it (causing them problems) or have to wait on the phone for hours trying to get someone to tell them where their W2 went or how to obtain a copy.
You are still on time to make sure your address is updated with your employer. If for some reason you cannot contact your prior employer then you should make an address change with the United State Postal Service (USPS.com) this way all your mail will be forwarded to your new address.