I have read Cash Flow Quadrant, Retire Young Retire Rich and Real Estate Riches.
I honestly think Rich Dad Poor Dad is the best book I have ever read. Totally changed my views on life and finance. His other books are good...but they get repetitive. The books that his "team" write (Real Estate Riches, Sales Dogs...etc) tend to be pretty vague and you'd be better reading another brand of book on the subject.
If you havent read "TRUMP: The art of the deal", do so. It's another fantastic book that will change some of your views. But like the Kiyosaki books, anything past The Art of the Comeback, are pretty much fluff.
Hope that helped some.