SoundClick.com is a great site. It has a lot of tools for the independent artist to promote his/herself. It also has a rating system with daily updated charts.
ReasonStation.net is a site for people who create music using Propellerheads Reason software. It's a great community of music producers of all levels and various genres. This is where I get some good critiques on the more techincal aspects of my tracks.
This is the official site of the makers of Reason, the software I use to create my tracks. I posted a few songs on their site early on.
Zed is a site that I am currently checking out. The user base is overseas and I'm looking into it to get a better international exposure.
