I finished I'm a Lebowski, You're a Lebowski: Life, The Big Lebowski, and What Have You by Bill Green, Ben Peskoe, Scott Shuffitt, and Will Russell, and I loved it. As I may have mentioned, a couple of the authors are the founders of Lebowski Fest, which is finally coming to Chicago this year (and of course is scheduled the weekend I will be out of town for a work retreat). Obviously, the book is geared towards Lebowski fans, and I would go so far as to say it's a "must read" for Lebowski fans. The authors interview all of the main characters and many of the smaller characters. In addition, they interview the inspirations behind several of the characters. It's hilarious that so much of the film (and the ridiculous scenes) are based on real-life people and events. If you're a fan of The Big Lebowski (and you should be), then you should definitely read the book.
My next book is A Heartbreaking Work of Staggering Genius by Dave Eggers. I've heard a lot of good things about it, so I figured I would see what all the fuss is about.