The following sites contain scores for hundreds of Cornish tunes, both traditional and recent tunes written in the tradition.
An Daras, the Cornish Folk Arts Project contains a wealth of information about the wider folk traditions of Cornwall. The list of Cornish tunes contains about 50 tunes, all with scores and many with MIDI files. It is run by Merv and Alison Davey, researchers and practitioners of Cornish music and dance since the 1970s.
The Kesson website is home to Kyt’s Tunery, perhaps the largest list of Cornish tunes available online. It is crowdsourced and growing, with over 200 tunes incorporating scores, xyz notation, and simple mp3 files. It is run by Kyt Davey.