You need to examine all the information you have about this person and then decide whether it is worthwhile to try to execute on the judgment. Here are some things to look for:

Cancelled checks. If you have any copies of checks from them, or cancelled checks you wrote them, and you can identify their bank account and account number, then you will want to contact a County Sheriff or City Marshall and ask about how to go about levying on the bank account. They will freeze the bank account and then take as much money as they can to pay your your judgment as well as their own fees.

Real Property. If you know this person owns real property somewhere, file the judgment in the county where it is located and it will automatically become a lien on that property.

Place of Employment. If you know where this person works, you can contact the City Marshall or County Sheriff and ask about how to go about garnishing their wages so that their employer is obligated to send you a portion of their paycheck each pay period.

Information subpoenas. Get a lawyer and issue information subpoenas to all banks where you think this person might have an account. The banks will have to respond whether they have an account for that person, then go to the step up top.

Private investigator. There are services that perform skip tracing and specialize in locating people. See how much they charge for their service and determine if it is worthwhile to invest in having a professional locate the judgment debtor. Note: They can also go to the post office and get a forwarding address if this person had his or her mail forwarded. For this last service, you can also contact a process server, as they routinely do this for relatively cheap.