This is not exactly what you ask for, but the URL

http://www.gre.ac.uk/~c.walshaw/abc/

Has a lot of links to Celtic sites with tunes in abc rather than MIDI format. Some of the sites have MIDI files too, I think.

I am not trying to push ABC over MIDI, but the information you are interested is contained in these files at these sites. The page also points to free software for playing abc files and for converting them to MIDI files.

Murray