Anthologies, Collections and Libraries: General Literature

Alex Catalog of Electronic Texts: Large collection of public domain books and documents from American and English literature as well as Western philosophy. Searchable by author, title, date, and content. Expanding constantly.
American Life Histories: Manuscripts from the Folklore Project, WPA Federal Writers' Project, 1936-1940 (searchable text): Manuscripts from the Federal Writers' Project, 1936-1940. From the Library of Congress files: a wealth of source material from the Depression Years. A goldmine for writing ideas, details, settings and more.
Bartleby Library: "The preeminent Internet publisher of literature, reference and verse , unlimited access to books and info on the web." Most comprehensive site for reference, poetry, fiction and non-fiction. Meets the needs of students, educators, and the intellectually curious.
Bibliomania: 2000+ texts of classic literature, drama, and poetry, detailed literature study guides, biographies, synonyms, reference tools.
Brautigan Virtual Library: Anyone who writes a book can have it added to the shelves of this library. Books accepted in any form (as long as they can sit quietly on a shelf). They are registered but there is no Dewey System. The author alone decides which shelf the book should go on.
Folger's Shakespeare Library: World's largest collection of Shakespeare's printed works, plus huge collection of other rare Renaissance books and manuscripts from all disciplines. Includes approximately 280,000 books and manuscripts; 27,000 paintings, drawings, engravings and prints; musical instruments, costumes and films.
Internet Classics Archive: Offers 441 works of classical literature by 59 different authors, including commentaries. Mainly Greco-Roman works, with some Chinese and Persian; all in English translation. Searchable and downloadable.
The Labyrinth: Resources for Medieval Studies: Massive, well-organized access to electronic resources in medieval studies. Easy-to-use menus and links provide connections to databases, services, texts, and images on other servers around the world. A Georgetown University project.
Library of Congress: Manuscript Reading Room: Makes available "approximately sixty million items in eleven thousand separate collections, including some of the greatest manuscript treasures of American history and culture" as well as support for scholarly research "in many aspects of political, cultural, and scientific history."
Literary Kicks: Beat Generation, Transcendentalists, French writers, Hippies & Latter-Day Beats and others incl. Ralph Ellison, the Harlem Renaissance, Haiku Masters, Salinger and more.
Online Medieval and Classical Library: Collection of some of the most important literary works of Classical and Medieval eras. Includes many links to other useful resources. [Note: My links to this site have been turning up "Cannot be found" screens here lately. If you have trouble, just Google Online Medieval and Classical Library and it should be the first entry.]
Questia: The World's Largest Online Library: Thorough, reliable research library for literature, humanities and social sciences; over 60,000 books and 1,000,000 journal, magazine, and newspaper articles, all searchable. Allows automatic creation of footnotes and bibliographies as well as other search, note-taking, and writing tools. The catch: For the most complete coverage, you need to subscribe.
RhymeZone: Much more than just a rhyming dictionary. You can search for quotations and even pictures. Includes complete texts of Shakespeare's works, The Bible, Declaration of Independence, US Constitution, nursery rhymes, etc.
UTEL (U of Toronto English Library): Extensive collection of works held in the U of Toronto English Library, searchable by author, title and first lines. Huge collection covering all major literary eras, with extensive links.
The Victorian Web: Comprehensive source for literary, social, political and economic information of the Victorian era, including a great many 19th century authors, visual and theatrical artists.
Western Folklife Center: A regional nonprofit folk arts organization dedicated to preserving, perpetuating, and presenting the diverse cultural heritage of the American West; includes cowboy poetry and other Western folklore.