ebooks

There a number of websites that permit you to download full or parts of books. 

Biodiversity Heritage Library (http://www.biodiversitylibrary.org/) - digitization project of major natural history museum libraries, botanical libraries and research institutes.  Permits downloading of early out of print materials

This link will take you to a page that provides about twenty such links (http://www.une.edu.au/library/resources/freeebooks.php