Download Free Ebooks » 21 Web 2.0 Book Sites to Explore. BookJetty is a social utility that connects you with your friends’ bookshelves and checks books’ availability in the libraries. It was started off as the creator’s pet project to solve the problems that were encountered, to log the books from the reading list in a spreadsheet and to frequently check books’ availability in the libraries. For a start, BookJetty links up with only Singapore National Library Board. Now, it connects with more than 300 libraries worldwide from 11 different countries, i.e. US, UK, Canada, Australia, Singapore, Taiwan, Hongkong, and more.