Today I finally got hold of a book I had been after for a few weeks: Pizzerías de valor patrimonial de Buenos Aires. It's a book on 39 pizzerias that are considered part of the city's heritage, with some photos and a little history and commentary for each spot.
The press run for the book was only 2000 copies and it sold out within a week of printing.
It took all my cunning to get a copy. Plus 35 pesos. All my cunning, plus 35 pesos.
The city has some of the book's content online. There is some good information there, but the site is poorly conceived and slow. It would probably just be easier for you to come here and see for yourself.