Zotero: The Tri-College Libraries recommend Zotero, a free online app that can format your bibliography, keep your citations organized, and even save your articles in the cloud so you can access them later from the library, home, or a cafe.
The American Anthropological Association produces this guide for contributors to its publications and for the wider audience of anthropology students and faculty. It is based on the Chicago Manual of Style.
See examples of formats in AAA style in this brief Trico guide.
The Chicago Manual is a comprehensive style manual used throughout the U.S. publishing world and contains much useful advice on matters of punctuation, capitalization, and word choice as well as on the documentation of sources.