Go check out a pretty good interview with Blizzard's Audio Director and Lead Composer Russell Brower of The Burning Crusade...
M4G: We hear instrumentation including harp, duduk, shakuhachi, flutes. Who are the live instrumentalists? Any other creative measures that factored into this truly timeless, organic sound you and your team accomplished?
Russell Brower: If it’s a solo wind instrument, you’re probably hearing master musician Pedro Eustache. This is our fifth major collaboration, and each session with him is a privilege and an event for our whole team of composers.
Read the Rest...
http://www.music4games.net/Features_Display.aspx?id=137