Liam's right: the best way to find a deal is at a gov. auction.
If you buy offline, you should get there with enough anticipation, take a good look at the cars and see who's there ( professional car dealers, other experienced buyers you might know of ). Best thing you can do is check as many auctions as you can fing in your local area, since that increases your chances of finding the right vehicle with almost no bidders.
You can have both a standard or extended guarantee on the cars you acquire, but they're usually in good conditions and papers are ok. In any case, always take with you a mechanic or someone who knows what he's talking about and check the VIN.
Here's more info on government auto auctions and again some more tips on government auction cars .
The best of luck to you.
