To get into opera, I always enjoy listening while reading the libretto in the original language next to its English translation. This site lists where to find these, organized by composer and opera.
Single-language pages are listed too, marked original or translation. Every link has an archived copy in case the source site goes offline.
Sources, side by side: LibrettoArchive, the late rwagner.net and Stanford's OperaGlass, offline since 2026 (both from the Wayback Machine; English and others), Kareol (original plus Spanish, hundreds of operas, indexed here under the original titles), and scanned printed libretti on the Internet Archive (the Ditson, Rullman, Schirmer and Ricordi bilingual booklets of 1830 to 1930), IMSLP (Handel wordbooks), the Library of Congress, and record-label booklets (Naxos, Hyperion, Chandos, Opera Rara, Harmonia Mundi, Brilliant Classics). Single-language pages: opera-guide.ch, opera-arias.com (originals and separate English translations), Libretti d'opera italiani (Italian, strong on the seventeenth and eighteenth centuries), and French Wikisource (mostly Offenbach). Not indexed per opera: The Book of 101 Opera Librettos (facing-page translations, borrowable). Something missing? Suggest a link.