If you want a review, ask for it
So, how do you get reviews on your site? How do you get reviews for a new product?
Just ask. Ask every buyer, every time, to review what they bought. (And you don’t need to pay, incentivize, or reward the reviews. They’ll do it just to be heard and to be helpful.)
Click on the image for a close-up of a great example in an order-confirmation email from Headsets.com.