Diana: Her True Story - In Her Own Words by Andrew Morton
A couple of weeks ago, I watched a PBS show titled Diana vs. The Queen. It was about the progression of their relationship, and it was fascinating. I did not know that Diana had known about Prince Charles' affair with Camilla before they were married and that Diana had thought about calling off the wedding. I was so fascinated that I immediately checked out this book so that I could find out more about Diana and her life.
If you're interested in royal life at all, you might like this book. It's quite thorough, and definitely pro-Diana. If you can though, I would recommend watching the show Diana vs. The Queen on your local PBS station when it airs next!