Analecta hymnica medii aevi
German hymnal by Guido Dreves, published in 1886 and available online through Open Library
CanticaNOVA
If you're involved in liturgical music, this site could be a valuable resource.
Hymn Tune Index
The HTI database contains all hymn tunes printed anywhere in the world with English-language texts up to 1820, and their publication history up to that date.
Liber Usualis online
Published by the Church Music Association of America, this is a file that can be downloaded to your hard drive.
Musica Sacra
Home page for the Church Music Association of America where you can download music, sheets, and find other information about sacred music.
NetHymnal
A search engine with over 10,000 Christian hymns,Author Bios, Composer Biographies, Hymn Histories and Gospel songs from many denominations.
