The Life of Cnæus Julius Agricola - Church and Brodribb translation. In HTML, with one paragraph per file. At Perseus. - http://www.perseus.tufts.edu/cgi-bin/ptext?lookup=Tac.+Ag.+1
The History - Church-Brodribb translation. HTML, each paragraph in its own file. Ability to view the Latin. At Perseus. - http://www.perseus.tufts.edu/cgi-bin/ptext?lookup=Tac.+Hist.+toc
Germany and Its Tribes - Church and Brodribb translation. HTML, with one paragraph per file. Ability to switch to the Latin. At Perseus. - http://www.perseus.tufts.edu/cgi-bin/ptext?lookup=Tac.+Ger.+1
A Dialogue on Oratory - Church-Brodribb translation. HTML, with one paragraph per file. At Perseus. - http://www.perseus.tufts.edu/cgi-bin/ptext?lookup=Tac.+Dial.+1
The Annals - Church and Brodribb translation. HTML, with each paragraph in its own file. Ability to switch to the Latin. At Perseus. - http://www.perseus.tufts.edu/cgi-bin/ptext?lookup=Tac.+Ann.+toc
Roman History (14-70 A.D.) - The Annals and The History. Church-Brodribb translation, using the paragraph numbering of the 1942 Modern Classics edition. HTML, one book per file. - http://mcadams.posc.mu.edu/txt/ah/tacitus/
The Works of Tacitus - Church-Brodribb translation, with parallel text in Latin. HTML, with ten paragraphs per file. At Internet Sacred Text Archive. - http://www.sacred-texts.com/cla/tac/index.htm
Tacitus on Germany - Thomas Gordon translation, from a 1910 edition. In plain text or as a zip file, from Project Gutenberg. - http://www.gutenberg.org/etext/2995
The Reign of Tiberius, out of the First Six Annals of Tacitus - Thomas Gordon translation, edited by Arthur Galton. Also includes translations of the Germania and Agricola. In plain text (two versions) or as a zip file. At Project Gutenberg. - http://www.gutenberg.org/etext/7959
The Histories - A history of the Roman Empire by Tacitus, written 109 AD and translated into English by Alfred John Church and William Jackson Brodribb. In HTML, with each book in its own file. Part of the Internet Classics Archive. - http://classics.mit.edu/Tacitus/histories.html
The Germany and the Agricola of Tacitus - The Oxford translation, revised, with notes. With an introduction by Edward Brooks, Jr. In plain text (two versions) or as a zip file. At Project Gutenberg. - http://www.gutenberg.org/etext/7524
Germania - English translation by Thomas Gordon. From an edition included in the Harvard Classics, 1910. In HTML, at the Medieval Sourcebook. - http://www.fordham.edu/halsall/basis/tacitus-germanygord.html