I just went to the Amazon main page, and it recommended that I buy this book:
Apparently Amazon doesn't realize that I already own that book. If you don't already own this book, I would strongly recommend it. I have at least 50 wedding planning books, but I think that this is the book that I found the most helpful. It's called The Wedding Book: The Big Book for Your Big Day by Mindy Weiss. Mindy Weiss is an amazing wedding planner. You may have heard of her before, she was responsible for Ellen DeGeneres and Portia De Rossi's beautiful wedding. This book contains a wonderful collection of information. It is full of great details, ideas, examples, and recommendations. It also includes lists of questions* to ask each of your vendors, which I found especially helpful. I honestly took either a list of written questions, or this book with me to every meeting I ever had with a potential wedding vendor. I know that a few of them teased me about my organizational skills at the time, but every single vendor at the wedding ended up complimenting us on what a pleasure it was to work at such a well organized event, and how impressed they were that things went so smoothly, especially without the help of a wedding planner or a coordinator. I don't think things would've gone nearly as smoothly without some of the tips I picked up from this book. If you only buy one wedding planning book, this is the one that I would recommend.
* Another book that had good lists of questions to ask your potential wedding vendors was this book: Bridal Bargains: Secrets to Throwing A Fantastic Wedding On A Realistic Budget. This link is for the new 2010 edition that will be released on November 15th. I used the 2009 edition, but every edition of this book has always received great reviews.