I highly recommend Gary Jennings' Aztec. It's a monstrously thick novel, 1100 pages in the standard paperback, but worth every word. Besides being a fairly accurate depiction of life in the Aztec world, there is also active mythology mixed in. In most of Jennings' novels, there are characters who appear in and out of the story to influence the protagonist, and their ambiguity of whether they are people with their own interests, or the gods and spirits from legend come again, is left for the reader. To expose you to all the levels of society and jobs, the protagonist is a sort of Forrest Gump character who participates in all of the major events of recorded Aztec history, from a childhood scribe to the eventual emissary to the Spanish.
However it's definitely not for the faint of heart. Jennings' books frequently have very graphic descriptions of various sex acts as well as violence. The Aztec world, where human sacrifice was commonplace, is no exception. If you can stomach the sex and gore, it's a fantastic read. I've read it about twelve times cover to cover and it's an adventure every time, Dickensian in detail and richness.
His Germanic Gothic novel Raptor, and his Eastern novel The Journeyer about Marco Polo are equally great.