I'm sure you've heard of it, but for those who haven't it's a great site! They have all kinds of wonderful eBooks! There's tons of e-books to choose from. You can explore the site and use a Backpack, download eBooks into it, and just have fun!
Here's a little song to get you started.
P.S. If you want more info on Evernote, watch this video. It's me explaining what it is: