hopefully soon there will be places everywhere to get bitcoins.  it's just going to take time to get the infastructure together.  for the moment, just use mtgox, they're the safest.  (until the Japanese government gets manhandled by the banking sector and forces it to close down... and don't think this is just a vague possibility - you can't even send paypal personal payments in Japan, because personal payments have been outlawed by japanese banks pressure on the reigning 'jimintou' right wing government.)