I think that "Folksongs and ballads popular in Ireland" (4 volumes) that Alison mentions is put out by Ossian Publications and edt. by John Loesberg.Ossian has a Web Site and they take overseas orders by mail (if you are outside of Ireland.
http://www.synergy.ie/OssianSite/Entry.html
The books have 50 songs in each of songs _popular_ in Ireland. They are not all Irish songs by a long shot. Its a good hit parade of stuff.
Soodlums Irish Ballad Book (Oak Publications Co 1982) is far more authoritative and I think a better buy but the book is not as handy to take to gigs and such as it is not as portable.
I dont think Oak has a Web Site, I wish they did.
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