A couple of years ago Dr. Anne Lorne Gillies mentioned in a Thread on Jim McLean's "Glencoe" that she was in the process of writing a book on Scottish Gaelic songs. Well, it was published recently, and it's a real beauty. Some details are:

"Songs of Gaelic Scotland" by Anne Lorne Gillies.
Birlinn [Edinburgh], 2005. 558 pages. Price £30 (available for £15 via Amazon UK).

CONTENTS
Muir is manran - Songs of the sea (35 songs).
Cinneadh is comhrag - Songs of clan and conflict (27 songs).
Fearann is fogradh - Songs of land and exile (27 songs)
Gaol is gradh - Songs of love (48 songs).
Spors is suirghe - Songs of courtship and convivialty (14 songs).

For each song is given: music, words in both Gaelic and English, historical/social background, informaton about the composer, and a list of available recordings of each song.

The book is a physically beautiful, quality production: a veritable treasure trove for anyone interested in Scots Gaelic language, music, literature or history.