[COPO]

Think like a detective (or hire one) and start with the previous owner and work backwards following all the leads. For title searches start with the state DMV where the car is registered now. Most have websites and you need to fill out the proper form and request copies of all titles and previous registrations. From there it might lead you to another state and then ou repeat the process. Unfortunately with privacy laws and the fact that many states are not cooperative or have purged records after 5-10 years the search often hits a dead end. There have been many discussions on this site for this topic. I would suggest doing a site search to get more ideas. Good luck.