Google’s Book Search is an ambitious project to digitise the world’s printed books. Although it has been dogged by various problems with copyright, the service is maturing nicely and is very useful for a wide range of research tasks.
The results come in a number of forms: book details without snippets, very tiny snippets, full-page previews for a limited number of pages per viewing, or full-view. For example, you can see all of these on the first page of the results for the “research strategy” query.
Helpfully, there is an option to restricted the search results to full-view books only. Furthermore, you can now download PDF scanned versions of many out-of-copyright books.
Not all out-of-copyright books are downloadable. It seems the only way to find them is to search with the “full-view” option, then click on the results and look for a “Download” button in the right-hand column. For example here is a version of Dante’s Inferno for which the PDF is downloadable.
Project Gutenberg has been making out-of-copyright works freely available for many years, but the project originated in the days of mainframes and flexible disks and the works are generally offered as text rather than in scanned form.
At Gary Price’s ResourceShelf there is a useful summary of other full-book resources including the World eBook Library, the International Children’s Digital Library, Shop ebrary, NetLibrary Text and Audio Books, The Online Books Page, The Open Access Text Archive and many more.