Guatemala City's Central Market is a 3-level underground maze, rehabilitated a few years ago to allow tourists one-stop shopping for handicrafts and other knick-knackery. There's a lot of competition and prices are fairly decent, though you do have to bargain and you have to have a ballpark idea of what a reasonable price is.

There are also a bunch of restaurants, many of which serve quite authentic Guatemalan cuisine, and all at very reasonable prices. At lunchtime it's popular with office workers from the neighborhood, which is a good sign.