The Chicago Manual of Style is an amazing resource. As an editor and writer, I use this resource often. The online subscription is even better. I have the online version. This tool covers all components of the technical parts of writing. If I am trying to remember if a comma needs to be placed in a certain area, it takes me three minutes to find the answer.

You won't go wrong with this investment. The online subscription is about $35 dollars. The book itself is more expensive. Whichever you prefer will come in handy.