I find that indie folk music is very relaxing. As well as artist such as We Are The City, Jason Collett and Coldplay and Switchfoot

Acoustic... try the following:
1) Amos Lee
2) Joseph Arthur
3) Bret Dennen
4) Kevin Devine
5) Adam Stephens

Relaxing Music
 

Alot of piano players on the smooth side relaxes me. Phil Casagrande , David Benoit does it for me

I've always found simon and Garfunkel very soothing. I love to watch the live in central park concert when I'm going to bed.

melodic death metal takes off a lot of the bite of stress on the weekends and I sleep a lot better on Sundays

The acoustic also sooths me a lot as well. I typically listen to instrumental acoustic to chill out, Antoine Dufour and Andy McKee are staples in my music collection.

Sleeping/resting to Eluvium, Hammock, Tim Hecker, Rosetta (Galilean Satellites mostly), or something like these is the greatest feeling in the world.

i listen to Andy McKee, i have never heard of Antoine Dufour but i'll check him out.

i also listen to The Script and BoyceAvenue if I want to relax because... well, it's a decent take at pop

If I'm in need of some relaxation, I usually throw on some Elliott Smith, Bright Eyes, Embrace, or Placebo.

Any new age music, specifically Chinese new age.

Ahhhhhhhhhmmmmmmmmnice.