how old are you looking for?? electro has been around since the early 80's, listen to "Planet Rock" from Afrika Bambaataa, that's an old one right there.. and it sounds nothing like the electro of today. even kernkraft 400 was considered electro. but it was the fusion with house music where things really started taking off. look at some classic benassi, royal gigolos, or global deejay. back in like 04-05, that's when the style started getting into what it is today. artists like kid dub, tocadisco, and trentemoller were tearing up the floor.