How to get the customers to pay for your advertising: Mercedes-Benz USA (MBUSA) has been testing its first iPod-compatible 'audio books' at the New York Auto Show.

Designed to brief potential buyers about new car features, the audio books provide in-depth digital 'walk-around' narrations through the familiar iPod MP3 player.

Show visitors can download the books to their own iPod for $US2.95 each, or use loaner iPods without charge. Downloads can also be bought on iPod maker Apple's itunes website.

The audio books project was developed by the MBUSA Training & Education Department which is donating all proceeds from sales during the New York show to the Automotive High School in Brooklyn.

MBUSA has developed four audio books that cover the M-class, CLS, SLK and SLK McLaren.