Here's few games which have awesome music:
Might & Magic 6-9
Heroes of Might & Magic 4
Morrowind
Baldur's gate trilogy (1,2,ToB)
Icewind dale 1-2
Dungeon Siege
Neverwinter Nights
Torment
Rainbow Six & Rogue Spear & Ghost Recon
Lands of Lore 3
Settlers 1-4
Total Annihilation
And here's few (movie) composers worth of listening...
Hans Zimmer (The Rock, Gladiator, M:I2, Peacemaker)
John Williams (Star Wars, Minority Report)
Basil Poledouris (Conan the barbarian)
Howard Shore (Lord of the rings)
E.S. Posthumus (Many trailers)
Oh... and here's a link for great site of FREE music!
HERE