There is a fantastic Metal documentary- Metal: A Headbanger's Journey.

http://www.metalhistory.com/metal01.html

This was really good- goes way back to the 70s and traces even the most current genres of metal to today. There's so much in Europe/Scandinavia right now that doesn't reach the US mainstream.

Currently stuck in my iPod:

As I Lay Dying - An Ocean Between Us, Fall of Ideals
I Killed the Prom Queen - Music of the Recently Deceased


Here's a graph from that documentary:



Click to enlarge...