Guatemala City has the best restaurant selection in the country, ranging from excellent local comedores (family diners) to ambitious contemporary restaurants in Zonas 9 and 10. The local food is hearty: pepián (a thick seed-based stew, often with chicken), kak'ik (a turkey soup from the Alta Verapaz, now common in the capital), chiles rellenos (stuffed peppers in tomato sauce), and jocon (chicken in a green tomatillo and cilantro sauce). Tortillas and black beans accompany almost everything.
Zona 10 — the so-called "Zona Viva" — has the highest concentration of restaurants, bars, and cafes, catering to the business and expat community. Prices here are higher than anywhere else in Guatemala but still cheap by international standards. Zona 14 (the upmarket residential zone extending south) has another cluster of good restaurants.
For local food at local prices, the comedores in Zona 1 near the central market, and the lunch spots around the bus terminal in Zona 4, are excellent. The indoor food court at the Mercado Central has dozens of stalls serving traditional dishes at very low prices.
Books: Like Water for Chocolate by Laura Esquivel (set in Mexico but influential across the region), and El Señor Presidente by Guatemalan Nobel laureate Miguel Ángel Asturias, are the two classic reads for the region — the latter gives an extraordinarily vivid portrait of fear and political power in Guatemala City.