If you dont feel like reading the motion comic version is really good:
They kind of did an animated watchmen... http://www.amazon.com/Watchmen-Complete-Motion-BD-Live-Blu-ray/dp/B001QFYLKS/ref=sr_1_1?ie=UTF8&qid=1382851857&sr=8-1&keywords=animated+watchmen
Watchmen is a graphic novel so the closest you are going to get to an audiobook is the motion comic, which you can view here or purchase here.