Have you guys heard about Pixels of Ink? It's a site that lets you know about FREE e-books that are available for Kindle and Nook. I have gotten a TON of really great books thanks to them.
They also have 2 sister sites: Inspired Reads & Pixels of Ink - Young Edition. Since I like Christian novels and teen literature also, I have also subscribed to these sites as well. You can either sign up for a daily e-mail alterting you to the new free books or you can "Like" them on Facebook and get updates that way.
Check it out!