"Music is the doctor of my soul." (Doobie Brothers)

General
All-Music Guide
Yahoo's Music Genera
Rough Guides to Music
Rolling Stone
NARAS the Grammys
tunes "The Intelligent Music Network"
100 most important American musical works of the 20th century NPR. Sound clips.

Legalities
BMI Broadcast Music Incorporated, representing songwriters, composers, and publishers
ASCAP American Society of Composers, Authors and Publishers
The Copyright Website