Public Domain Resources

As music loses its copyright, it is posted through online open-source sites. These sites can be valuable resources to teachers who need to find a classical text out of print, or simply working on a tight budget.

The Lied, Art Song, and Choral Texts Page - Public Domain Choral Scores

http://www.recmusic.org/lieder/

The IMSLP / Petrucci Music Library - "The free public domain music library."

http://imslp.org/wiki