Since you're new to the style, I'm going to give you a massive list of bands in the melodic/progressive/power realm:
Adamantra
Anubis Gate
Anthriel
Appearance of Nothing
Arch Nemesis
Ashent
Astra
Aspera
Awake
Before Eden
Borealis
Broadmoor
Caesar
Circus Maximus
Cloudscape
Conception
Coexistence
Damnation Angels
Darkwater
DGM
Disdain
Edgend
Elegacy
Emberstorm
Epysode
Eumeria
Everfest
Evergrace
Evergrey
Eyefear
Forcentury
Forgin' Fate
Forever's Edge
Future is Tomorrow
Hammerforce
Heavenfall
Kamelot
Kategory V
King Misfit
Illusion Suite
Incrave
Infinita Symphonia
Innosense
Invictus
Lanfear
Lost in Thought
Manegance
Mindguard
Mirrormaze
Mindwarp Chamber
Myrath
Nation Beyond
Pathosray
Platitude
Prowlers (the)
7days
Red Circuit
Serenity
Seventh Wonder
Silent Call
Silent Memorial
Southern Cross
Stargate
Status Minor
Symakya
Symphony X
Tomorrow's Eve
Transcending Mortality
Vanishing Point
Veloce Historia
Winterborn
Wiszdom Stone
Hopefully some of these will pull you into the style.
Clint/Site Manager
Metal CD Ratings