"Perseus is an evolving digital library, engineering interactions through time, space, and language. Our primary goal is to bring a wide range of source materials to as large an audience as possible. We anticipate that greater accessibility to the sources for the study of the humanities will strengthen the quality of questions, lead to new avenues of research, and connect more people through the connection of ideas."
Google Book Search "Search the full text of books and discover new ones"
Internet Public Library links to book sites
The Oxford Shakespeare 1914 Oxford edition of the Complete Works of William Shakespeare, easily accessed and searchable
All reference books! Encyclopedias, dictionaries, books on quotations and English usage, anatomy, Fannie Farmer's 1918 cookbook, Emily Post's 1922 Etiquette, Parliamentary procedure and government... Nonfiction has the inaugural addresses of all the presidents, works of Confucius, Marcus Aurelius, Milton, Roosevelt... You just need to go and look.