I was wondering if anyone knew if there was a site that would give you Japanese artists based on American artists you like.

I'm trying to listen to more Japanese bands, and I think that would be really useful.

I wish I could find a band with the same feel as Hollywood Undead, but that's probably unlikely

hmm Hollywood Undead is kinda punkish right? I really don't know how else I'd classify them. I've got a few of their songs on my IPOD ^_^ I don't know of any sites that let you search by the American artist you like but there is one site that I go to to keep up on Japanese music. Jpop Asia is a site of pop/rap/R&B/anime music and also a bunch of CHinese and Korean bands as well.... I'm sure you could ask around on the forums there too if after looking around a little bit you couldn't find what you are looking for ^_^. Good luck

Stop the pink everywhere...

last.fm is great for finding j-music. Start with the tags j-punk, j-indie, j-rock, j-hiphop... and just keep going from there. Never listened to hollywood undead until now, but there are several j-bands with a somewhat similar sound.

Lots of good recs here:
http://forum.koohii.com/showthread.php?tid=1649