How can your parents who live in New Jersey place a lien on your ex-husband's home in North Carolina or is there another option for recovering the 6500.00 debt?

The party owed the debt would need to file a lawsuit against the debtor in the state court in the county where the debtor resides. Other then a voluntary payment of a debt such as the one described there is no other way to recover monies owed except through the legal procedure as prescribed by the state in which the debtor resides.