I know I've said this before, but Ian Anderson should've had a hand in composing the score (and would be even more desirable for The Hobbit). This was quite a fun exercise. Oh, and I didn't use any songs with obvious Middle-earth references (like Led Zep's Battle of Evermore), because, well, it would be cheating. Here's some suggestions:
FIRST SCENE WELCOMING US INTO THE SHIRE:
Jethro Tull -- One Brown Mouse
http://www.youtube.com/watch?v=UcUS4qaXZFU
FRODO AND SAM BEGIN THEIR JOURNEY IN THE SHIRE:
Jethro Tull -- Life is a Long Song
http://www.youtube.com/watch?v=h8nak...eature=related
IN THE OLD FOREST MEETING BOMBADIL:
Jethro Tull -- The Whistler
http://www.youtube.com/watch?v=w3Q2L1Tt1Hk
ASCENDING TO WEATHERTOP:
Jethro Tull -- Dun Ringill
http://www.youtube.com/watch?v=JuPQ3oHB4e4
A WALK THROUGH LORIEN:
Led Zepellin -- Bron-Yr-Aur
http://www.youtube.com/watch?v=y-WRt...eature=related
SCENE WHERE ARWEN IS A WIDOW AND WALKS ALONE THROUGH LORIEN:
King Crimson -- Moon Child
http://www.youtube.com/watch?v=iw0eduoVGw4
THE BOAT RIDE DOWN THE ANDUIN:
Mason Williams -- Classical Gas
http://www.youtube.com/watch?v=mguzK...eature=related
SARUMAN'S ARMY MARCHING TO HELM'S DEEP:
Alice Cooper -- Halo of Flies (Prior to the vocals)
http://www.youtube.com/watch?v=n_pgClrEs9c
THE MARCH OF THE ENTS
Ian Anderson -- Fly by Night
http://www.youtube.com/watch?v=M8Ubj...eature=related
THE SIGNAL OF MINAS MORGUL AND SAURON'S ARMY MARCHES:
Black Sabbath -- War Pigs
http://www.youtube.com/watch?v=0GRR_n_yQGA
SURVEYING THE DEAD AFTER THE BATTLE OF PELENNOR FIELD:
Pink Floyd -- Great Gig Sky in the Sky
http://www.youtube.com/watch?v=Enwnt7-j90k
IN THE HOUSES OF HEALING:
Genesis -- Entangled
http://www.youtube.com/watch?v=inblU...eature=related
SHELOB:
Alice Cooper -- The Black Widow (after the priceless Vincent Price intro)
http://www.youtube.com/watch?v=JVHUy...eature=related
FRODO AND SAM BEGINNING THEIR ASCENT OF MOUNT DOOM:
Fairport Convention -- Reynardine
http://www.youtube.com/watch?v=O3RMu...eature=related
WITHIN MOUNT DOOM:
Genesis -- Dance on a Volcano
http://www.youtube.com/watch?v=xfA0z6eK8uQ
THE BLACK GATES OPEN AND SAURON UNLEASHES HIS LEGIONS:
Peter Gabriel -- Here Comes the Flood
http://www.youtube.com/watch?v=RQYlK...eature=related
ARAGORN AND ARWEN'S MARRIAGE IN MINAS TIRITH:
Yes -- And You and I
http://www.youtube.com/watch?v=tpXv-...eature=related
SAM WATCHES ROSIE COTTON AND FALLS IN LOVE:
Fairport Convention -- She Moved Through The Fair
http://www.youtube.com/watch?v=D8SwU...eature=related
FRODO BOARDS THE GRAY SHIP AND SAILS INTO THE WEST
Alan Parson's Project -- Time
http://www.youtube.com/watch?v=nvwrSdMY7dQ
Okay, I have to stop myself. I could do this all day (and I'm getting angry looks).