I get bored often and I just happen to find official streams of Japanese artists once in a while, so why don't we all post when we find our favorite Asian artists, even if its the music label's accounts?
Note these are all music videos
http://www.youtube.com/user/flyingDOGch?ob=0&feature=results_main Flying Dog (music label)
http://www.youtube.com/user/maayasakamotoCh Yes, as one can see, it's Maaya Sakamoto!
http://www.youtube.com/user/kingrecords?feature=watch King Records (music label), who knows you might even find three Nana Mizuki music videos!