If you are a power metal fan you should try this bands(my personal opinion):
Hammerfall
Avantasia
Helloween(i am sure you already know them)
Gamma Ray
Edguy
Powerwolf
Iron Savior
Blind Guardian
Axenstar
Falconer(i know only the "Falconer" album but i find it great)
Heavenly(a really good band from France)
Iron Mask
Kamelot
Sabaton
Sonata Arctica(one of my favorite bands)
Stratovarius
Unleash The Archers
Mystic Prophecy
Well , I would say Finntroll,Unleash The Archers(power+melodic death metal band from Vancouver),Sonata Arctica,Ensiferum and Dream Theater.
I'm into folk metal lately .