Man this post is old as fudge! Thought I'd update it. With some of the new artist I've been listening to that some people may not have heard of yet.
Electro House Artist (In No Particular Order):
Wolfgang Gartner, Madeon, Dillon Francis, Porter Robinson, Knife Party, Far Too Loud, Kill Paris, Digital Freq and Pyramyth, Electric Soul Slide, Belzebass, NEUS, Ryeland, Rogue, Firebeatz, Dirty Loud, Joe Gartson, Electrixx, Gemini, Cold Blank, Savant, Adventure Club, Ton!c AKA Deorro, Krewella, and J-Trick.