I stumbled upon this site where there's books of all kinds....good ones of all kinds....that you can download. I've so far gotten books on some science stuff as well as PC "Fix It Books". When you download them, you'll have to use the "Free Mode". Sometimes it'll say "come back later", "download unsucessful" etc... but refresh the page or come back to it in a bit and it should work fine. It did for me anyway. It's just trying to sell you the "faster" download method. It might take you a little bit of time, but I say it's worth it, for the books you can get! Reading a "book" on a computer or e-reader isn't the same as a good "old fashioned" book though.

http://www.ebooksdownloadfree.com/