gamegirl--
It is a little frustrating isn't it? Some authors (I know John Grisham is one) will not allow their books to be published in any type of e-book format. My guess is that their worried about piracy.
Personally, I like to listen to audiobooks as well as read e-books, so if a book is available in audio format, but not in e-book format, I'll listen to it instead.
You might want to check out the New York Public Library's website. They have ALOT of adobe e-books available for checkout. As I live in California, I was able to apply for a library card by paying a non-resident fee of $100 for one year. Because of their huge selection of titles available for download, I consider it a bargain.
dordale