I also choose the ABC path. It is relatively easy to take a sheet of music, Joe and type in the ABC equivalent. It is almost as if you were trying to describe the music to a friend over the telephone.
You can write multi-voiced music with it, including chords. The only thing you can't do (at the moment, anyway) is to have different tone coloring in the different voices.
As has been mentioned, there is a LOT of music in ABC. Especially if you are into Celtic. For some reason the people who collect Celtic tunes have been the ones to set up website with ABC files.