Bill, where are you?
UPDATE: If you know where Bill is, please don't post his contact info here or anywhere publicly. But I would appreciate it if you could ask Bill to get in touch with me.
UPDATE: Gareth Branwyn says:
I talked to Bill! He actually goes by the name William now. He sounds really good. It was a little awkward at first, not having talked in over tens years, but we warmed up pretty quickly. He said he needed to take the time off, step out of the limelight for awhile. He doesn't have Internet on his ranch, so he's been somewhat out of touch with the online world. But the awesome news is that he's back doing art and he's working on a new book and website! He hopes to launch the site in September. He'll send Boing Boing more info as it's available. It was so great to hear his voice, I almost choked up. It's been way too long. (BTW: His friend David read Mark's post and the comments to Bill over the phone. He was touched by all of the memories of Schwa that people shared and the kind words about his art).