Free Sheet Music
A gigantic repository of scanned public-domain scores for Classical music up to the
early 20th-Century. Conforms to Canadian copyright laws which are in some instances a little more permissive than
the U.S.
John Mamoun scanned a bunch of public-domain editions of piano music, and he offers them here in PDF form.
Specializes in choral music.
An open source music project for scores and recordings.
These scores are all set using lilypond.