Japan has been in serious trouble since the 9.0 earthquake and tsunami occurred on Friday, March 11th, 2011. Coupled with the nuclear uncertainty going on – Japan really does need all of the money and help that they can get.
Traveling to Japan is going to be pretty much completely out of the question.
Donating supplies and money is the way to help.
Google has a great page that they are keeping updated here:
http://www.google.com/crisisresponse/japanquake2011.html