Two things you can do:

1. Pray for survivors, rescue workers, and the grieving

2. Give toward disaster relief

The international mission board disaster relief is nearly unique in that all costs for raising funds and for infrastructure is covered by churches before hand.  Every dollar donated goes directly to relief at the disaster specified.  Distribution and administration is done by folks already in the area partnering with nationals who know where help is most needed.

If you wish to participate, and to receive a tax deduction, please Click here and look for the Japan Response Fund.