Can be found in "The Manx National Songbook" Vol II, edited by Charles Guard. Here's a customer review I found on Google:

The Manx National Songbook

The title isn't an exaggeration

When I asked the owner of a musical instrument store on the Promenade in Douglas, Isle of Man, about Manx songbooks, he handed me a paperback copy of "The Manx National Songbook, Combined Vols I & II." He said, "It's a bit expensive, but it's the only one." There are in fact other books of Manx music ("Kiaull yn Theay," for example), but I don't know of a collection in print of anywhere near the scope of TMNS.

The book is in two volumes. The first was published in 1896 and edited by W.H. Gill, and the second in 1979 by Charles Guard. Both are collections of songs in English from and about the Island. The first volume in particular seems to consist primarily of songs from the traditional Gaelic oral literature, with English lyrics translated or "adapted" from the original. The original Manx title is given under the title in small print in quotes, with a translation of the original title in italics. A suspicious number of the songs have lyrics (or even music) by W.H. Gill, the editor. A Celtic-culture purist would be frustrated by Mr. Gill's careful insertion of himself in between the reader and the source material. Indeed, Stowell and O'Breaslain, in "A Short History of the Manx Language," dismiss Gill's songbook as "drawing room arrangements with dashes of sentimentality in the English words," aimed at a wide audience, in contrast with A.W. Moore's contemporaneous "Manx Ballads and Music," which presented original lyrics and music with English translations (and which, alas, I didn't learn of in time to look for it on the Island). Among the old-as-the-hills Gaelic folk tunes here is "Ellan Vannin," which seems to be among the favorites of the Manx folk (many wanted it as the national anthem), and which has been performed by Douglas' famous sons, the Bee Gees.

Volume II is an effort to continue Gill's work. The source material seems to be generally written in English, by composers from the Victorian period on, writing songs from *or about* the Isle of Man. There's a handful of early-20th-c. songs by Englishmen about vacationing on the Isle (for the golden age of the Isle of Man as a tourism destination seems to have begun with the advent of affordable sea travel and ended with the advent of affordable air travel), such as "The Dear Old Isle of Man". This section also includes the Manx National Anthem, set to an adapted traditional Manx tune with lyrics by none other than our old friend W.H. Gill. And the last few pieces ("Give Me the Bus Fare to Laxey") seem to be recent compositions that say, "Hey, lookit me! I'm a song from the Isle of Man! Whoo hoo!"