Here is a useful site posted by one of my contacts in Japan.
For those members that have friends in Japan, this may help you located them.
http://japan.person-finder.appspot.com/?lang=ja [1]
My classmates from Japan are scattered all over the world.
Some of them have returned to Japan though.
I hope that your friends in Japan are safe and sound.
Regards,
Balifly
Links:
[1] http://japan.person-finder.appspot.com/?lang=ja