If you're just getting started, you can get everything you need to begin a wholesaling business using Matt's ebook that you can get for free on this website (subscribe to receive from the home page).
All of the other strategies are just spin's on a very simple investing technique. Until you do a few deals the hands on way, I would not recommend buying any systems that promise too much automation. You have to understand the fundamentals first, and Matt's free guide will give you all that.
Any questions you have along the way you can post here and get answers from any of us that have experience and monitor these forums.