Moon Song by Elen Sentier seems to fit the bill:

"When Isoldé hears that her lifelong hero, Celtic folk singer Tristan Talorc, has just committed suicide, it strikes home and makes the oppressive London, where she works just after “nine-eleven”, feel nearly as oppressive as the Belfast of The Troubles where she grew up. Fate intervenes when an ex-boyfriend offers her a job with him down in Exeter in the West Country. And so begins her enchanted journey to find the lost song of Tristan Talorc, the Moon Song..."

LFF