While you are at Northwestern Law, you have access to Lexis Advance. Use your log in credentials to sign in, then click "Public Records" from the home page. Note this database has terms of conditions for its use; be sure you read and comply with them.
While at Northwestern Law, you have access to Bloomberg Law, which has integrated with PACER. PACER is the federal court system's electronic records database. Log in to Bloomberg then click Litigation & Dockets the Docket Search.
Last Known Address
A person has moved may have left a forwarding address. Send an envelope to the last known address and write "ADDRESS CORRECTION REQUESTED / DO NOT FORWARD" on it. If the post office has a forwarding address on file, it will put a correction label on the envelope and return it to you.
Contact the person's friends or relatives, as well as the current or last known employer and ask if they have a current address.
More Public Records
Departments of Motor Vehicles (DMV)
Register of Deeds/County Recorders Offices (if the person owned property)
City and County Tax Departments (look up local government's website where the person lived)
State and local business records (contact the state office that regulates businesses/corporate compliance, trade names, or commerce)
Trade or Professional Licensing entities (Members of a regulated trade or profession, such as a barber, dentist, nurse, doctor, or private investigator, may be certified, licensed, or registered through a state agency.)
VINELink is a service that provides victims, or anyone, with information about an offender's custody status, court dates, sex offender registry status online or by phone 877-884-8463. Includes County and Municipal jails. Alternatively, you could contact the state's Department of Corrections directly.