I actually use music as a sleep aid quite a bit and even have a whole ipod playlist called "Sleepy". I'll just throw out a couple, though.
Most of this soundtrack works for me, but this is my favorite off of there:
Ditto on most of Millenium Actress' Soundtrack. One of my all-time favorite albums actually since this music is very moody to me and takes me to a different consciousness.
Love the Survivor Soundtrack, too. Perfect mix of atmospheric and epic.
And no videos for this last one, but these songs are pretty much instant-sleep for me:
www.moodflow.com/
They have EXCELLENT wallpapers too. I always go there to grab backgrounds for work. <3