If the defendant is still on probation you will need to contact the probation department for District Court at 989-831-7434, Circuit Court at 989-831-7353, or Juvenile Court at 989-831-7308 - and ask for the probation officer who is assigned to the case. The probation officer can help you get your money if restitution was a condition of the defendant's probation and if the defendant is still on probation.
If the defendant is no longer on probation and your restitution has not been paid in full, see a private lawyer. A criminal case restitution order is a court order that expires only when the restitution has been paid in full. If the court-ordered restitution covers all of your claims, then you do not have to separately sue the defendant. You can enforce the criminal's case's restitution order like any civil judgment. The Clerk's Office for the court that the defendant was sentenced in may be able to help you or may already be attempting to enforce that order. Call District Court at 989-831-7450, Circuit Court at 989-831-3520, and Juvenile Court at 989-831-7308.