I read his The Power of Now a while back. He gave me a lot of new insights! I am not a deep believer in any one philosophical view or person, I'm still discovering (and probably will be for the rest of my life), but he has certainly taught me the power of living in the moment. It feels absolutely great! If it wasn't for him, I would now not be looking at trees in complete awe and joy when I'm waiting for the bus to arrive (for example). Sadly I'm not always living in the moment, there tend to be specific moments, usually when I'm waiting for something/someone. It's so easy to "forget" about living in the moment.. There should be a post specifically about this! (Maybe there is one already :o )
Have you read any of Steve Pavlina's articles? (stevepavlina.com) He has a bunch of great material as well. He writes about a bunch of different topics, but they're all related to "personal development". Maybe I'll post something about him.
Also one of my current favourites is the law of attraction. I have begun to experiment with it lately. Steve has plenty of articles on that too. Or maybe you've read Rhonda Byrne's books as well?