Consumer law question in Ontario, Canada. I know this is US forum but my question pertains to methods of location a person.

So i bough a car 3 months back (BMW 745i), the seller was pushy; he wanted me to pay him right away. I got the car checked by my mechanic and the only thing needed replacedment were the brakes. He agreed to get them replaced but he needed the money to buy himself another car which he had out a deposit on. I paid him in full after the initial deposit and i was to get the posession to the car the day after. Few days later he tells me the brakes have been changed but his mechanic found problems with the car which would take atleast $6,000 to fix. I demanded my money back and he agreed.

Its been 3 months and i still haven't gotten my money back. I had two phone numbers of him both have been cancelled. He changed his address and the only communication i have is through email which he replies to barely once a week. He still promises to return the money - just doesn't deliver.

Long story short, i gave him the money and i don't have the possession nor the title.
To serve him in small claims court here i need his address or any contact information where he could be reached. I have nothing.
I have a written Agreement with the stated amount. I also have proof of payment in form of a cheque.
HOW can i locate this person so that i could take him to the small claims court. Is there anything that could be done.