Miata Wiring Diagrams might help. Probably not a bad idea to invest in a Mazda Factory Service Manual either. They have the best wiring diagrams.
Note: The Factory Service Manual is invaluable however, it is not for the newbie mechanic as it assumes a certain level of automotive expertise. It is not a step-by-step guide like Haynes or The Enthusiast's Shop Manual. It is more in-depth though, compared to these books.