I have found a great Net Radio which plays Tolkien music: http://www.middle-earthradio.com/

Unfortunately I just found out that this station is currently off-line, but I do hope that if will be back on-line soon!

There you can listen to various kind of music, the "harder" styles such as Heavy Metal, and the "softer" styles such as Folk and New Age, and other radio broadcasts such as audio books and recordings of Tolkien himself. I myself love the most the "softer" streams. There you can listen to all the music of the Trilogy movie soundtracks, the music composed by Howard Shore, and many other interesting artists and their music inspired by the Middle-earth. For example a little speeches by Christopher Lee reading some Tolkien poetry from the books, which I really love.

"A Elbereth Gilthoniel, silivren penna míriel o menel aglar elenath! Na-chaered palan-díriel o galadhremmin ennorath, Fanuilos, le linnathon nef aear, sí nef aearon!"

"Elen síla lúmenn´ omentielvo!" - "A star shines on the hour of our meeting!"

"Nai tiruvantel ar varyuvantel i Valar tielyanna nu vilya!" - "May the Valar protect you on your path under the sky!"