The International Music Score Library Project (IMSLP) is a project for the creation of a virtual library of music scores and recordings. The library consists mainly of scans of old musical editions out of copyright. In addition, it admits scores by contemporary composers who wish to share their music with the world by releasing it under a Creative Commons license. It also includes included public domain and licensed sound recordings.
Internet Archive is a non-profit library of millions of free books, movies, software, music, websites, and more.
Online since 2003, IPA Source is the web's largest library of International Phonetic Alphabet (IPA) transcriptions and literal translations of opera arias and art song texts. Now with over 7075 texts including 1216 aria texts.