The Internet Music Score Library Project is an online library of public-domain sheet music. Most of the available music is in PDF format and can be freely downloaded. The files are uploaded by users, mostly scanned from published sheet music that falls into the public domain. This means mostly compositions that are old enough to be public domain, in published editions that are also old enough to be public domain.
This is a fantastic resource for finding older editions of woodwind solo pieces, chamber music, and orchestral parts. Go to this page to find music for specific instruments or ensembles, or jump straight to one of these:
If you don’t find the piece you’re looking for, it may be worth doing a search of the site, since the lists are updated manually. Bear in mind that music as recent as the twentieth century is mostly too new to be public domain. If you’re a student, chances are good that your teacher will want to to purchase his or her current preferred edition ($$$), rather than use these.
Because the music is user-uploaded, not everything is of consistent quality and usefulness. Scanning quality varies, and the editions available online may or may not suit your needs. Some of the solo concerti, for example, are available only as a full orchestral score. And there are oddities like the listing for the Glazunov saxophone concerto, which is currently available on the IMSLP only in a clarinet transcription. In the future, it’s likely that the selection will improve as users upload more scans.
I’ve updated my essential woodwind solo literature listings to include links to IMSLP files where available.
Thank you to Feldmahler and the other IMSLP users and administrators for making this available!