Towing Issues: legally tow or boot car?, duplicate title, co signer

Question
hello, (New York City, NY)
The situtation is I am co-signer/co-owner of a car with a friend whom has defaulted on the car payments.  I can't find her anywhere, she moved somewhere and no phone to reach her by, and she has the car.  I don't have any paperwork that says I own the car but I will be getting a copy of the contract i signed stating I am co-signer/co-owner in a few days and I hope to go to DMV tomorrow to apply for a duplicate title.  I also suspect the plates on the car dont belong to the car.  I am not the registered owner of the car but I am on the title.

My question is if I do find the car, can I legally have it towed or have a boot placed on it without any paperwork?  If I need paperwork, will the title and contract be enough? And if towing or boot is possible, can it be made sure she can't take the car once its locked up?

Answer
Well I am going to have to pass on this question as it is more a legal question right now as to if you have the rights to tow or boot the vehicle... I would check with a lawyer as to your specific rights, as it sounds like you are planning to repo the vehicle..

Sorry that I can not provide you much more information