I'd like to name 100 bands, but the first that come to mind are
Manowar - The epitome of what is metal, surprised I didn't see them on any of the other lists. Wagner inspired riffs, top musicianship and the best vocalist to ever grace heavy metal.
Judas Priest - The band that single handedly created what we came to know as heavy metal (no, despite what you may have heard it wasn't sabbath

). The riffs, the solos, the screaming vocals, all tm by da Priest.
Jag Panzer - American Power metal at it's best.
Dokken - I'm surprised to see Dokken is nearly forgotten nowadays, the man's released some of the best hard rock/metal hybrids of all time: Back for the Attack, Under Lock and Key etcetc. George Lynch is a god!
Fifth Angel - When it comes to melodic virtuoso metal, fifth angel's debut is simply second to none, and perhaps the best metal record ever released.
Grave Digger - A personal fave, in your face barbaric german metal that sends all smurf power pussies back to the kindergarden that spawned them!! Especially when they listen to Boltendahls sheep like BLUAAAAAAAARRR screams
Yngwie Malmsteen - The man that re-invented the post Blackmore neoclassical guitar. I prefer his earlier work with Soto and Boals.
Iced Earth - Because Stormrider is the best 90's metal album, and because the triplet of Stormrider, Burnt Offerings and Dark Saga just can't be beat!
Candlemass - FUCKING DOOOOOOOOOM!!!!
Axel Rudi Pell - The Blackmore of heavy metal, the man's released incredible albums like Masquerade Ball or Magic. Plus he has some of the best cd covers ever!
Brocas Helm - The gods of deranged epic metal, just listen to their latest (Defender of the Crown) and bow before Schumacher's moustache!
Manilla Road - Crystal Logic is the epitome of technical, atmospheric and generally kick ass epic metal!
Skyclad - Founders of the folk metal genre and some of the most intelligent lyrics ever
Bonfire - Because German poser kicks american poser ass!!
3 inches of blood - BECAUSE THEY WILL DOMINATE THE METAL SCENE IN AEONS TO COME! METAL, LEATHER SPIKES AND SWORDS!! AAAARGGGHH ... gah, gah... sorry caps
