Metal: A Headbanger's Journey

right...of course, you could interview mostly old thrash bands, and then interview newer thrash bands.
in general you could just not interview slipknot.

Metallica, Slayer, Anthrax, Exodus, Godsmack, Hatebreed, Megadeth, Testament, Overkill, Death Angel, Shadows Fall, Meshuggah, In Flames, Strapping Young Lad, Stone Sour, Superjoint Ritual, Lamb of God, Vio-lence, Kreator, Sodom, Destruction , Nuclear Assault, Voivod, Chimaira, Biohazard, Fozzy/WWE Superstar Chris Jericho, Sepultura, Kittie, The Haunted, DRI, Soilwork, Killswitch Engage, Heathen, Hirax, Brian Slagel, Jon & Marsha Zazula
Bands interviewed.
How about some interviews with teh black metals?

And there is never, ever, ever any reason to interview Godsmack.