Huh, I've never actually bothered to use Google Book search. I'll e-mail you some stuff shortly, but here's another topic for thought: can we find any more stylistic characteristics for the genre aside from its association with underground art, its roots in punk and punk forms (hardcore and post-punk), and the fact that, judging by their lyrics, a lot of the artists seem to be miserable bastards (I love how the 1990 EW link makes a point of this)?