I just read that book. A relevant story in it is this bit on Spider-Man:
While Ditko has had a point about being co-creator of Spider-Man, he went off the deep end long ago, turning into a Ayn Rand-worshipping lunatic. He wrote a full length comic a few years ago ("The Avenging Mind") that went on at length about Marvel and their practices, that was just batshit insane to read. He's been producing new stuff on his own for years, but it's almost entirely unreadable garbage. A shame, really.