The U.S. Postal Service is warning Hoosiers of a scam that promises an edge in the job market, for a price.Georgia-based Testing Authority offers a so-called study guide to help pass the postal exam with the promise of a full-time job, Call 6's Rafael Sanchez reported."I thought I was careful. It looked legit with postal service logos all over it," said Christina Cox, who paid $129.95 for the guide. "You can't trust them."When Call 6 tried to contact the company, the phone number was disconnected and a recording said the number dialed was invalid.A spokeswoman for the USPS said the agency is concerned about the scheme because it's in the process of cutting jobs due to a decrease in demand."We are not hiring any full-time workers at the U.S. Postal Service," said Kim Yates. "Those ads are not endorsed by the postal service, nor representative of what we do here."She said the USPS does not post job positions in newspapers, and that all of the information included in the study guide is offered for free at Indiana libraries.