One of the most interesting aspects of the digital books revolution is the growing number of personal memoirs, regimental histories and local histories becoming available. Public domain libraries like Project Gutenberg, ManyBooks, Google Books and FeedBooks offer these books in electronic formats including ePub. The Internet Archive is also a good source, just a bit more difficult to navigate. These sites allow us to collect and maintain a collection of books supporting our research without taking up floorspace. And . . . they are all searchable!
To manage your collection, take a look at Calibre [see Meet Calibre]. To keep up with new content being added to these libraries, you can subscribe to their recent books feeds.