Martin, are the slender paperbacks "Folksongs of Dublin" by Frank Harte, "Folksongs of Ulster" by Robin Morton, "Folksongs of Cork", etc still available? I think they were published by Ossian; I have them myself, but think they're nice little collections for folks that can't afford the Sam Henry.

Another collection more readily available in the US is:
"Soodlum's Irish Ballad Book" (pub. by Oak, I think) a mix of traditional and modern songs with tunes; it has scanty notes and some nice photos.