Tip #1: Be prepared to not get a response from an email. They dont give a darn and the clerk that opens the emails will be clueless as to who to send it to.
Tip #2: A face to face visit is better by far. Look into their eyes and all you will see is hair roots. Ask for a supervisor when they drool.
Tip #3: There is an inspection station (NOT safety inspection) that looks at cars coming off of salvage title, etc. Those guys are the most knowledgeable and usually one or more of them are hot rodders. Take a picture of the car with you to show it. They will tell you the real skinny. Write it down. Get their name and phone number so you can beg their help later when you hit one of the deadbeats.
been there, done that, still pissed
mike in tucson