Led Zeppelin (some of there work are metal, but there mostly a hard rock band)
KISS (70's) in the 80's they were just glam metal
Late 60's bands like Iron Butterfly, Cream, Stepponwolf (though they did help create metal but I still don't consider them metal)
Guns n Roses (after the Appetite for Destruction Album)
Limp Bizkit (terrible example of nu metal as well)
Kid Rock (actually, he's mostly anything, rock, rap, country)
Alice Cooper (70's)
Nu Metal on the other hand, I'm not gonna abuse it saying sucks "JUST BECAUSE IT'S NOT METAl" I'm not ignorant so I don't think it sucks, It is metal BUT, it is very very different, yes it's the opposite of what metal is but, back in the late 60's rock n roll was opposite to what rock n roll sounded like in the 50's and people loved it. Things can't always sound the same, they change and I (don't mean to brag) as a fair person am welling to except that. Go ahead, call me not metal, but I know Priest more than you do.