I checked another site I use and there are people who have sent money and materials to get signed (not just buying one of his pix) as far back as July 2010 with no response. That's on the address on his website.
He is still doing conventions, and just did the Hollywood Collectors Expo last year - and that's not mentioned on his page.
You might want to send an email and ask them if he's still signing. The email address is on that page.