I sent a Q+A and SAE with US Stamp on to Rod on: 29th March 2015, and a few months later, I didn't get my Q+A back, he sent me a signed and personalised photo instead, still really happy.
Address I used was:
His home address in USA
The return address on the return envelope was:
Stiefel Entertainment,
21731, Ventura Boulevard,
Suite 300,
Woodland Hills
CA 91364
USA