Net Galley is free for librarians, booksellers and reviewers, etc. The publishers pay to have books put up on the site. You request a book and see if the publisher deems your request worthy (I've received all 3 books I've requested) and if so, give you their viewing options. They include a kindle edition, *
It seems like a good program and prompted me to restart my Wyvern's Peak Writing blog so I have a place to blog about my cooking experiences (among other things).
*It turns out what I remembered as epub was actually an unprotected PDF download.