Any good J-Pop bands o artists for beginners?

I've been a diehard anime fan for a long time now so I sort of gained interest in Japanese música too. Really, I've only been listening to Kyary Pamyu Pamyu and VOCALOID, and I'd really like to try branching out my interests, so any suggestions? I'm a pretty big fan of música with a beat, techno music, dubstep music, basically anything that gets tu pumped, but I'd be willing to try other things!