I'm not sure how you should go about purchasing/financing. Ask your parents for some advice there. Two things to remember though--first, you need good credit and it is good to establish credit. This proves to other creditors that you can pay back what you borrow. It will help you down the road. Second, if you can save and pay cash for something you should. Don't live off of credit.
So, what exactly are you doing? You say that you are a good video editor and that you want to learn After Effects. Are you a filmmaker? Or do you consider yourself just an editor/FX guy? This may help determine what you need.
If you are as serious as you sound you probably want one of the prosumer 3CCD cams. Here is a great article comparing 3 of the newer cams--Sony's new HDV FX1, Canon XL2 and Panasonic DVX100A. Sony's VX2100 and Canon's GL2 should also be on your list. Sony's FX1 does High Def video, which is beautiful, but it looks like video, not film. If you are trying to create a film look for future display on large screens you should consider the DVX100A.
http://www.dvxuser.com/articles/shoot3/
I'm not sure how you feel about buying used equipment, but if you get the cash together or get a bank loan you can look around for used cams. It's not just teens who get into a hobby and then drop it. A lot of people think they are going to be the next (insert big director's name here) and buy tons of equipment and then it just doesn't happen. Check
http://www.craigslist.org for used XL2, DVX100, GL2s, VX2100. Craigslist has local areas and you can meet face to fact to make the deal.
As for the computer, do you think you could get by with an iMac G5? I think the iMac could handle FCP and After Effects, but I don't think it can run Motion well, if at all. Not sure if you'll want to play with Motion. A Power Mac gives you more room for growth and probably more productivity with real time rendering and faster DVD encoding. Check Apple's special deals page under the online store for refurbs of the previous models.
Here are the standard prices. I guess EDU prices are a bit lower. You also may be eligible for the upgrade price for Production Suite if you already own FCP. A final thing to consider is starting out with Final Cut Express and iDVD. You've been doing FCP for years so you'll know more than us if you *need* FCP or if you can get by with FCE.
Panasonic DVX100A 3500 (from b&h photo video)
PowerMac Dual 2.5 refurb 2599
20" Cinema display 999
Production Suite 1299
TOTAL 8397
Panasonic DVX100A 3500
20" iMac G5 refurb 1699
Production Suite 1299
TOTAL 6198