Free wiring diagrams and Technical Service Bulletins, a huge database, here>
http://www.bbbind.com/technical.html
On the page under "technical information", click on
TSB's and wiring diagrams, next page-agree to end user license agreement, next page-click on wiring diagrams, then enter year, make, model, and engine size. Then pick the system (engine, brakes, lighting, etc.) and the subsystem if applicable. Every circuit on your car! You just have to keep returning to search page, and enter vehicle info again to see another system or subsystem.