Hey Mhockey, I was kinda freaking out about the same thing. I am coming back to school (been in combat zones for the last 6 years).
The first thing I would recommend: Talk to the graduate advisor. Call up the department, get his/her number and make an appointment. Read up on gradute and department admissions too and write down concerns.
Then meet the grad advisor in person, a Professor, and lay out what you are trying to do. I am my case (Engineering Undergrad - going for Physics PhD) there are a few courses he recommended I take and then we did up a quick course plan. He also gave me key dates, and other good to know general info and addressed all of my concerns.
In my case he recommended delaying I guess we could call "formal" grad standing to 2011, but in the interim I would have this special student status (which I didnt even know existed) where I could take grad clases and other high level undergrad without the typical pre-reqs - AND they have some TA/RA work for me where I had my strengths in the department.
I guess the moral of the story is talk to the grad advisor, in person if possible.