Microsoft have just added the beta version of their book search option to Live Search. At present there isn't a link from the home page, so you won't be able to run a book search until after you have tried a preliminary websearch. It is then possible to use the "more" drop down menu to access the book search feature - although I found that this doesn't work properly in all browsers. Still a useful alternative to Google Book Search and Amazon's A9 that enables the reader to download the entire text and not just read the context on a single page. Interestingly it appears to include the complete text of some works which must still be in copyright. A further weakness which will become apparent as more publications are added is that it isn't possible to refine the search by author or title.