I was reading this much linked-to Lynda Barry profile from the New York Times, and the article mentioned that she'd been a guest half a dozen times in David Letterman's show. It turns out that one of these interviews was uploaded to YouTube less than a week ago. The interview (ostensibly to promote Barry's book The Fun House) is from 1988, when she had recently moved to New York.
The first volume of a ten-volume set reprinting Lynda Barry's work, Blabber Blabber Blabber, will be published by Drawn & Quarterly in November.
UPDATE: Mike Lynch had already posted it.