They are in ABC code which is used by lots of musicians to swap tunes.

Load a suitable programme from http://abcnotation.com/software

Copy and paste the whole abc file into it and you should be able to see the notes and hear the tune.

Eventually a lot of the Village Music Project collections will be also available in pdf format but it's not a priority for us. Others can take the code and put it in more accessible formats. We just do the initial work of finding and transcribing the books.