Depending on which make.If its a bike or car. There are Haynes or Chilton manuals available in most motor acessory shops or the web. Try Halfords; that's if you live in the UK or go at E-Bay....
If you bought it new, it should come with the car when you bought it. But if it's not, you can just ask VW local dealer or in some parts shop. If they don't have it on stock, they could just probably...