Librarian Allan Symons said the service, called 'One Click Digital', will cater to a wide audience and a diverse range of digital devices.
"They've got a pretty diverse range of titles and they'll obviously be increasing as they go along," he said.
"This opens the world up, really."
Members can download audio books from 'One Click Digital' to their laptop, tablet device or mobile phone.
Library manager Jan Richards of Central West Libraries said: "The new range of audio downloads includes over 600 popular titles by well known international writers of thrillers, crime, or romance novels as well as biographies, about travel and self help. It's all part of our plan to provide library access anywhere, anytime."
Central West Libraries is also launching free access to 'Transparent Language Online', a service offering more than 80 languages through comprehensive self-paced learning programs.
Mr Symons said the service will make it easier to access language resources.
Visit Central West Libraries' website www.cwl.nsw.gov.au for links to 'One Click Digital' and 'Transparent Language Online' from the library catalogue or the Info at Home menu.