I use a site called realtytrac at http://www.realtytrac.com . They compile very comprehensive information about REOs, foreclosures, etc. You can get basic information for free to get a sense of their service, and then buy a subscription if you're serious about going forward with a purchase. The information they include is the current owner's name and contact information, foreclosure status, lender information, etc. It's a fantastic resource.
It's well worth the investment--I got a yearly sub for under $100, and I think they also offer month-to-month subscriptions.