If you still are in possession of the stolen goods, contact the local authorities and advise them that you were involved in a Shipping scam.
If you already shipped the goods, but have not cashed the check from the fraudulent company, contact the authorities to inform them of the situation; provide them with the check and any emails that you received so that you may file a report.
Notify your bank immediately if you have deposited a fraudulent check or received a transfer of funds. If the funds have not cleared, have the charges reversed.
Maintain any evidence that you have regarding the scam  and file a claim with the FBI Internet Crime Complaint Center (IC3) or National Consumers League
If you replied to a posting from CareerBuilder.com, notify Trust and Site Security so that we can take action immediately. Be aware that many emails claim that the company is advertised on Careerbuilder.com; however a great majority of these emails are spoofed, and not derived from the Careerbuilder.com database.