Aztec social climate differed from contemporary society by the things that were valued. Specifically, Aztecs valued gold less and cacao more. Mayans similarly valued cacao highly, and it figured significantly in trade for goods from other societies.
You might wish to view the film Apocalypto, directed by Mel Gibson, for an insight into the social structure of the Mayan culture and the way that it was built so much upon conquest and colonising other tribes. It also paints a picture of a religious theocracy where priests were incredibly important individuals. This might help you to gain greater understanding of the kind of society of both Mayan and Aztec civilisations.
Both civilizations were, it would seem, rigidly hierarchical, and religion played an important role in both. An interesting topic might be to compare and contrast exactly how and why the two civilizations responded as they did to the threats they faced.
Researching the general topic of the Aztecs and Mayans should be relatively easy, because both civilizations are well known and were highly important. One factor to keep in mind is that all civilizations evolve over time, so you want to make sure that you are comparing and contrasting the two cultures at comparable periods of their development.
It's easy to forget that eNotes itself has plenty of good material available on practically any topic. I thought I would do a little digging for you and list the links that looked most helpful. Always be sure to look for the bibliographical information cited in any source.
Socially and politically, these were pretty similar peoples. Both were ruled by monarchs who were at the top of a social structure. In both cases, priests were high on the social structure and religion was used to bolster the legitimacy of the rulers. Both had religions in which human sacrifice was very important.