Get the 9th edition of
Linux for Dummies free, from Wiley Publishers. The regular price is $22.99.
Here's the linkage:
http://www.tradepub.com/?p=w_wile142...0&ts=0&u=0&e=0.
There's potential for even more freebies from Wiley. There is a link near the bottom of the page that is preceded by "Other Resources from: Wiley." If you click on it, a page comes up with lots of freebie ebooks. Most of them are samples, excerpts,
et al., but from just skimming over the selection, it looks like there may be some real ebooks there.