PhilippaMention of Callanan reminds me. I recently came across a book called "History of verse translation from Irish 17??-189?" (not sure of the dates but it basically covers 19C.) by a man called Welch, around 1988. It started life as a Ph.D. thesis - so its not light reading. But it seems to have a lot of info on the various published collections of translations of poetry/song and good critical analysis. Seems to be still available e.g. at Kenny's Bookshop of Galway, who have a website.
Regards