FACEBOOK - Beetailer - If you already have an online store with services like Magento, Amazon Webstore, Shopify or PrestaShop, you can create a Facebook shop using the Beetailer app. It automatically pulls product information from your current catalog so there's no need to list items. Just choose the products you want to feature and Beetailer creates a customizable shop tab on your page.

http://www.entrepreneur.com/article/228146