Find a GMID vertificate from someone if you can. If not, there are pleanty of dealers that will sell at or just below invoice. With the 08's just starting to show up, the dealers will not want to hang onto the 07's. Deal with the sales manager only.
visit
http://www.edmunds.com/ to check for the latest incentives.
If you cannot get 9K or 10K off sticker, I'd be suprised. You won;t get that much off with 0%, but the cost saving mey be worth it if you can get a low enough rate.
Where are you located, some of the members here may be able to point you to a good contact.