Thanks to Becca, I just got off the phone with Rupert. I'll have the whole interview up here shortly, but Rupert asked me to pass along this information.
If you are going to write him, please do not use any address you may have pulled up off the internet. They do not get to him.
You may send letters to either the PO box that Becca set up for him, or to him directly at:
1075 Broad Ripple Ave
Indianapolis, IN 46220
And he says to PLEASE include a self-addressed, stamped envelope if you are requesting a signed photo or return letter.
He is endeavoring to respond to every letter that he's been sent, but he's running a few weeks behind right now. So, if you sent him something, or are planning to, expect a couple of weeks' delay.
And he said THANK YOU to everyone for the support and the cards and letters. And he also said the "Send Rupert A Dollar" campaign is also great, because he's using that money to pay for the photos and stamps to respond to everyone who wrote.