You can find the same information by going to your local county or city courthouse and going through the land records. You can find properties on which back taxes are owed, ones that have liens on them by the county or city, and so forth. The TV infomericals simply tell you how to track it down more easily. However, the great deals are few and far between. Yes, you can buy some property for as little as a few hundred or few thousand dollars, but the improvements are likely to be condemned, and the land itself may be land-locked, or in a flood plain, or in some other way undesirable. But, like I said, all that information is publicly available from your county or city.
If you want to get the "How to Make a Million in Your Sleep" kits inexpensively, go to Ebay. Lots of people sell the programs they bought there; I've gotten some good deals on them. You ought to be able to save 50%-80%, on average.
Having said that, the programs/kits generally are accurate as far as they go, but they usually don't give you enough information to complete the whole transaction. So, if you buy directly from the infomerical, make sure there's a real guarantee: Not: "Try this for 30 days and if you can document you've tried our system and it hasn't worked for you, return it for a refund." Instead: "No questions asked 30 days guaranteed refund."
Hope that helps answer your questions.