Depends on how you want to go about it. You can buy all the parts used from either a junk yard or some of the guys on here. Or you can buy a full parts car if you have the space, use the parts, and recoup some costs by selling the remaining scrap.
When I did mine I got quoted around 700-800 for all the parts used I think. Instead I bought a 5 speed E36 and sold the cats and extra stuff and scrapped the rest. Ended up breaking even if not making a couple hundred bucks.
@nate - don't have the time or space to deal with a parts car
@MadChigga - yeah, I trust Jay
@AlpinaMan - I don't have their number and am lazy. Figured they could pm me as they're always on the board and isn't that kinda the reason for having a sub-forum for their shop?
I usually reply to emails within the hour; if you're looking for a timely answer and phone calls aren't for you (or you like a paper trail) e-mail always works best.