Hi!
As 4getmenottreasures said, I'm working with Lauren, Vanessa, Morgan, Sarah, and some other admin to determine the best way to use Etsy to organize around causes to help in the wake of cataclysmic events.
The first step though, a name to your cause, you seem to have figured out quite well. JoyforJapan, fantastic.
I would suggest members and supporters use this tag on Treasuries created to recognize the tragedy and feature items whose proceeds are going to charity.
You can also use this term JoyforJapan as a tag on items whose proceeds are being donated to charity.
Starting a blog to communicate your cause is also a good place to start!
Again, to reach me directly shoot me a Convo. I check my convos very regularly; it's an easier and faster way to get me a message. I'll post back with more information though when I have it.