Having genealogical reference books on hand while researching your family tree can be helpful. If you don't have the room for a fully-stocked library of traditional books, you might want to consider looking into building your ebook collection. These days even genealogy books can be found in ebook form on a variety of sites.
The Google eBookstore is a good place to start your search for genealogy-related ebooks. While the name seems to imply that it is a place to purchase ebooks, Google actually has nearly 3 million free titles available in addition to the ebooks they sell. You can download the ebook to your compatible phone, eReader or even your home computer to read at your leisure.
Searching "genealogy" in the free books returns 14 pages of results to choose from, including books on the surnames Lyman, Habersham, Ewing, Henry, Nutting and Douglas, just to name a few. Searching "family history" gives you 13 pages of results, including local histories.
Project Gutenberg is another place to check for free ebooks. It offers visitors a choice of over 330,000 ebooks. This site doesn't appear to have as much genealogical material as Google, but it's still worth a look.
Both Amazon and Barnes & Noble offer free ebooks. Once you have completed your search of the ebooks on either site, just click on sort by price low to high to bring the free ones to the top of the list.