What you can do is check out page 4 of the attached link: http://www.judiciary.state.nj.us/prose/10282_collect_money_jdgmnt.pdf
The relevant text says:
If you do not know where the judgment debtor
has a savings or checking account, what personal property the debtor owns, or where the debtor works, you may obtain an information subpoena from the Office of the Special Civil Part Clerk. An information subpoena is a court paper containing a written set of questions about the debtor's assets.
You may serve an original and one copy of an information subpoena upon the debtor either personally or by registered or certified mail, return receipt requested, and simultaneously by regular mail. You also must provide a postage-paid, self-addressed envelope with the information subpoena. The debtor must answer and return the information subpoena to you within 14 days from the date on which it was served. An information subpoena cannot be served more than once in a six month period without approval of the court. If the debtor does not answer the information subpoena, he or she is subject to contempt sanctions enforceable by the court.
If the debtor has not fully answered this information subpoena within 21 days from the date on which it was served, you may make an application supported by a certification to the court for an order allowing you to serve a separate information subpoena upon banking institutions, employers or businesses who owe money to the debtor. If the court signs the order, this information subpoena may also be obtained from the office of the Special Civil Part. You may then serve an original and one copy of this information subpoena either personally or by registered or certified mail, return receipt requested, and simultaneously by regular mail. You must also provide a postage-paid, self-addressed envelope. If a party upon whom this information subpoena is served does not provide written answers within 14 days from the date it was served, they are subject to sanctions enforceable by the court.
Another fantastic information kit for you is found at:
Other general information can be found at:
I hop this is of help to you. Best wishes! It's always a challenge in collecting a judgment but if you take the time to review this information, the court clerks will help you along the way. They can't give you legal advice, but they will show you the forms so that you don't fall between the cracks