"being a reproduction in facsimile of the first folio edition, 1623, from the Chatsworth copy in the possession of the Duke of Devonshire, K.G." You will have to provide your email address; a link with the file (a zip file) will be sent to you.
"The Shakespeare Quartos Archive is a digital collection of pre-1642 editions of William Shakespeare's plays." This archive is a partnership among the Folger Shakespeare Library, the Bodleian Library of the University of Oxford, Maryland Institute for Technology in the Humanities (MITH) of the University of Maryland, British Library, University of Edinburgh Library, Huntington Library, National Library of Scotland, and Shakespeare Institute of the University of Birmingham.
The EEBO contains the full text of 100,000 early English works from 1470-1700. The subject areas include: English literature, history, philosophy, linguistics, theology, music, fine arts, education, mathematics, and science
Internet Archive, an Internet library which provides permanent access to all kinds of literature and formats, has numerous editions of William Shakespeare's works (16th century to 20th century). These works are available in multiple formats such as PDF (images of the actual work), read online, and full text.
Nineteenth Century Collections Online (NCCO) provides full-text, fully searchable content from a wide range of primary sources for the "long" 19th century, 1789-1914. NCCO indexes the full text of books, newspapers, pamphlets, manuscripts, maps, diaries, photographs, statistics, literature, government reports, treaties, and other kinds of documents in both Western and non-Western languages. Released incrementally beginning in 2012, NCCO's first four topical collections include: British Politics and Society; Asia and the West: Diplomacy and Cultural Exchange; British Theatre, Music, and Literature: High and Popular Culture; and European Literature, 1790-1840: The Corvey Collection.
The Horace Howard Furness Shakespeare Library scanned books in its collection which are available online. One way to find Shakespeare's plays and poems (from the 16th, 17th, 18th, and 19th centuries) is to 1. select "Browse Furness" tab 2. select "Browse Authors" 3. select "Shakespeare, William, 1564-1616".
All eight volumes of Shakespearean Prompt-Books of the Seventeenth Century are available online. The prompt-books are presented as facsimiles. The online version contains the introduction, collations, and acts as found in the print version. It is possible to perform a search within the prompt-books. Mullen Library also has Volumes 3, 5, 6, and 8 in Stacks Folios (PR2757 .E8).
The eight volumes are Volume I (General Introduction and Macbeth), Volume II (Measure for Measure and The Winter's Tale), Volume III (The Comedy of Errors and Midsummer Night's Dream), Volume IV (Hamlet), Volume V (Macbeth), Volume VI (Othello), Volume VII (Midsummer Night's Dream), Volume VIII (King Lear, Henry VIII, The Merry Wives of Windsor, Twelfth Night, The Comedy of Errors, and The Winter's Tale).
Most of the texts listed on these sites are in the public domain.
ebooks@Adelaide provides a short bibliography for William Shakespeare, full text to his works in categories (comedies romances, histories, tragedies, and poetry), and other links. The University of Adelaide in Australia maintains this website.
Project Gutenberg (invented in 1971) is an online book catalog which allows browsing by author, title, language, categories, or recently added and searching by author or title. This website is " the first and largest single collection of free electronic books". Project Gutenberg has numerous editions of Shakespeare's works in English and in other languages such as German and Finnish.
Electronic Literature Foundation (ELF) maintains The Plays of William Shakespeare. ELF has the full text of all of Shakespeare's plays (tragedies, histories, and comedies). "Each play has its own search engine, concordance, quotes, and other information."
The Modern English Collection of the Electronic Text Center provides access to material (in full text) from 1500 to the present. You can browse by the last name of an author such as Shakespeare or by area of interest.
George Mason University maintains the Open Source Shakespeare which is the result of a M.A. thesis. This website has the full text of Shakespeare's plays, sonnets, and poems and allows you to perform a search for a word in the text, concordance, and character. The layout of Open Source Shakespeare is based on power, flexibility, friendliness, and openness.