Ex-spouse refuses to give me vehicle awarded to me in divorce. What can I do?

Shortly after my ex-spouse and I separated, I traveled out of state for the holidays. While I was gone, ex came back with a friend, took my BRAND NEW motorcycle (pushed off a cliff / sold / gave away / who knows) and disappeared. I tried and tried to call, but had no new contact information. Months later, I received divorce papers, and couter-claimed. Then months after that, we came to an agreement and the divorce was finalized. I was awarded my truck and motorcycle, and ex got the car. We both signed the decree, and a month later, when I asked for my motorcycle, all I got was, "I don't have it." Now, I'm at a huge $ loss. Can I receive a check for it, or another one just like it? What do I need to do?