My son has a clasic car that is registered in his name that is in his mothers back yard and she will not let him retrive it. Is a court order needed??

I'd hope that this could be taken care of without a court order.  I'm not an Indiana attorney, and I'm sure that there's a lot more to this than you were able to put into the question, but on general principals, I'd say that while your son's mother has the right to keep him off her land, she doesn't have the right to keep his car away from him.

Your son should go to the police department for where his mother lives, with the title for the car (and the registration or a duplicate, if he has it), and ask if an officer will escort him onto the property to retrieve it, as an alternative to charging his mother with stealing his car.  Of course, the paperwork needs to be in order, insurance and plates in place, etc.!  Most police officers prefer keeping things simple, and should be able to understand that he wants his car back but would rather not have to have his mother arrested to get it.

If that doesn't work, it's time to talk to a lawyer.  One place to find qualified attorneys is our website, http://attorneypages.com