I'm in the same situation. What I have done since the creditor was contacting me on a daily basis trying to collect money from me, I asked them if I was in the contract as an owner. They told me yes. As soon as I verify that I was in the contract, I did the following two things:
1. Went to my local Tax office and requested a copy of the renewal registration receipt. It cost me a couple dollars. All you need is your driver's license.
2. Requested a copy of the title from the lien holder which is the credit company. I also made sure my name was there as an owner as well.
These two things enpowered me to go and tow the car away from her. I knew where she worked, so I went and picked it up and had it delivered straight to the car dealer.
Once in the car dealer, I had new keys cut and reprogrammed.
Right now I'm going to take the next step. I'm going to try to collect some signatures from her to get an extension to skip the next payment since Chrismas is around the corner. I had to pay the payment she was behind with. In order to get the extension on the Dec. payment and the signature on her releasing ownership of the car, I'm going to give her the option to cooperate with me or else I'm going to have to sue her. As long as you can prove that she is in default and that she can afford the payment you have the case won. You can look me up for my original Thread. Just do a search under Mercury Mountaineer and my user name is pec0001. You'll like it.