immigration.gov is pretty good. Go to forms, I 485 and they have all the package required. We had to send our medical with ours, but we are in NJ. Get your medical stuff straight, if you have insurance, go to your primary doc early, get all your INS required shots and X ray if you didn't have one recently. Immigration docs are pricey and they want you to do it there.
Also, Be sure to check the fees the day you send your stuff. I was pretty bummed when my application came back because the fees changed for some reason within who weeks( they went down??? and then went up again when we filed, can you believe it?) That was the only reason.