Hi Sharon, looks like it's available via Amazon from Tradition Records, according to Liam's site. Hope you can get what you need following this link.

http://www.liamclancy.com/recs/early.htm


The site showed the playlist is 46(!) songs, so there's no easy answer to your source question. Lots of their material is traditional, some is modified traditional, some composed.

You can get a lot of info on any particular song if you use the Search window on the Mudcat homepage, keying in one song title at a time.