American Sacred Music
19th and early 20th century sacred music published in the United States, with a focus on music from the Midwest. In addition to hymns and anthems, the collection includes cantatas, revival songs, and other types of sacred music.
American Vernacular Music Manuscripts, ca. 1730-1910 (AVMM)
Manuscript music documenting American musical culture from the Colonial period until the early 20th century, from the collections of the American Antiquarian Society and the Center for Popular Music. The digital collection contains about 350 music manuscripts (with 10,000+ pieces of music), including song and tunebooks, sheet music, and commonplace books.
Christian Classics Ethereal Library Hymn Tune Library
Hymn Resources on the Internet
Hymn Tune Index
Hymnal Net
Hymnary.org: a comprehensive index of hymns and hymnals
Hymns and Spiritual Songs
HymnSite.com
Hymn Society in the United States and Canada
Name That Hymn
Net Hymnal/Cyber Hymnal
Musiksammlung der Württembergischen Landesbibliothek
The music collections of the Württembergische Landesbibliothek, including archives of monastic music, hymns and choir books, and the archives of Württemberg Court Theatre ca. 1750-1935.
Oremus Hymnal: Index of The New English Hymnal, 1986
Theological Commons
Digitized books, periodicals, and audio recordings related to theology and religion. Subcollections include the Benson Collection of Hymnals and Hymnology, the Payne Theological Seminary and A.M.E. (African Methodist Episcopal) Church Archive, and the T.F. Torrance Collection of Antiquarian Books (including materials related to the history of Christianity in Scotland).
The list of links above is courtesy of Murl M. Winters, Associate Library Director at Evangel University