The Chicago (Turabian) Style of writing is almost identical to MLA Style.
Both are generally considered interchangable for Humanities papers.
The main caution from my experience is not to mix them up in the same paper.
You can find many good guides to their usage and differences online.
For a more detailed description of Chicago Style I would recommend "A Manual for Writers of Research Papers, Theses and Dissertations" by Kate Turabian. It is in at least it's 7th Edition, and if you are going to write lots of papers will come in handy to buy from Amazon, for one or two uses, your local or school library may have a copy.