It's not a question of whether you derive financial benefit, but of whether you publish in any way (and technically that would include public performance, I suspect, though nobody is going to worry about small-scale amateur stuff). Tolkien's work will be in copyright for a good while yet. I'd guess that many of those settings out there (I agree, most are self-indulgent crap) are unauthorised and, frankly, I hope the estate chases the cheeky bastards. Screw up your courage and send them yours; they might like it.

It just goes to show how meaningless the term "celtic" has become, though, when you see how often it's applied to Tolkien's books. The man himself intended the Elvish songs to be something on the lines of Gregorian chant, which would explain Clinton's comment. Tolkien may well not have been much of a singer. I'm not a great fan of Donald Swann's settings (the book was The Road Goes Ever On) but they were intelligent and expertly made. From my point of view, the best settings I've heard were in the BBC radio adaptation of The Hobbit in the late '60s or early '70s; early-music style arrangements with harps, shawms and the like, and choruses sung in parallel fifths. Evocative stuff, and very English.