Directories
ABC Collections, Easy Sheet Music - Free Sheet Music Links, Ed's Music Resources, Festival Singers - Choral Sheet Music Download Sit, Find Free Sheet Music, FreeSheetMusicGuide, The, Meantone.com, Mundial Directory, Musica Viva, Sheet Music Web
Free Arrangements
Delcamp.Net, Free Guitar, The, Free-Scores.com, Jay Buckey Music, Mfiles, Music and You, My Sheet Music, Nissimo, Printable sheet music in PDF format, Score On Line
Manuscripts
Chazzanut Online, Henry Purcell, Historic American Sheet Music, Music for the Nation: American Sheet Music, 1870-1, Sheet Music from Canada's Past, The ap Huw manuscript, The Lester S. Levy Sheet Music Collection, UNC-Chapel Hill Music Library 19-th Century Ameri, Vatican renaissance music exhibit
Original Compositions
African-American Sheet Music from Brown University, Alamance CreekMusic, Ben Marcato, Debbie Major, Free Piano Sheet Music, G. F. Mlely Originals, New Standards for Piano by Ned Gerhart
Public Domain
247 Sheet Music, Anne's Free Sheet Music, bagpipetunes.net, Breizh Partitions, Cipoo, Free Sheet Music Source, Mutopia, Petrucci Project, The, Ragtime Sheet Music and Books, RowyNet
8notes.com
Collection and directory of free sheet music pieces and lessons for piano, guitar, violin and other instruments.
Abacci Music
Irish, celtic and world sheet music, midi files and tab.
Anyscore
Mainly commercial sheet music with some free downloads. Includes self-published scores by living composers.
BlankSheetMusic.net
Blank sheet music to print for free, supports multiple keys and formats, guitar and bass tabs too.
Music Sheaf
Features manuscript staff paper in several customizable formats.
NotaViva
Free pieces in PDF format by various Classical composers as well as educational music.
Online Music Scores
Links to scores which may be downloaded free of charge, collected by Howard J. Callon, music professor at McGill University in Seattle, Washington.
Sibelius Music
Showcase site for the Sibelius plugin 'Scorch' - includes several thousand pay-per-download files and some free users files.