http://www.baen.com/library/
Excellent place! They've got "seed" books, ... and I'll use my current favorite author as an example. David Weber. They've got the first two books for the Honor Harrington series available in HTML download. No cost.
Made an iSilo conversion VERY easy (set for 2 links deep and convert, while you're reading chapter one.). Overall size of the book ended up at around 400kb for "The Honor Of The Queen", the second book of the series.
Overall, they have I *think* around 20 authors who've "donated". So far, I'm still going through David Webers's stuff (not simply because of his last name, either.
) and he's excellent. I am planning on going back to THIS site for quite some time.
One nice thing about ebooks, though. I don't get ink smeared all over my fingers by the end of the day after reading an ebook. Must be something about the new paperbacks these days (I liked what I read of the first two books from Mr. Weber and I went out about bought the first 8 books of the Honor Harrington series in paperback form, despite already having the ebook form of the first two. They were THAT good. )