Royalty-Free Music for Performances

So many old plays, including commedia dell'arte style shows, have instructions for music to be performed, without offering any suggested music. Copyright has been extended so long that most people don't even know any public domain songs outside Christmas carols or opera anymore. How do you find legal songs to play if you can't afford royalties on popular favorites? Below you'll find several collections brimming with music you can legally perform for free, and in many cases you will able to select period-correct tunes for the era of the show you're performing.

The Semantic Index of North American, British and Irish traditional instrumental music with annotations, formerly known as The Fiddler's Companion. Lists old tunes and provides a score if known. 

Provides recordings, sheet music, and textbooks to the public for free, without copyright restrictions. Put simply, their mission is to set music free. Features classical music recordings and sheet music.

The International Music Score Library Project. Music scores and sometimes recordings, some of it surprisingly obscure and desirable, all of it public domain or creative commons.

A huge archive of traditional, folk & old music -- song-books with lyrics & chords, tune-books, sheet-music, scores, old songs, midi backing tracks, tabs, music lessons & theory, learn to play guides for various instruments, chord diagrams, scales and other music educational and academic reference materials.

Excellent for finding Renaissance tunes -- if applicable, and the tune is known, the archive offers a recording of each ballad being sung, making it great for those who can't read music.

Public domain choral music -- great for finding medieval music. The goal of CPDL is to host a large collection of music scores and other supporting files (such as midi or other sound files) which can be freely downloaded and used. Most of the scores on CPDL are modern editions based on older works whose copyright has lapsed (or which are otherwise in the public domain), but some scores are newly composed and offered for download by the composer.