If you're online shop owner you must meet some law requirements. Especially if you're located in European Union country. If you're looking for addons that will provide some cookies informations, will met EU payment process specification - check this article.
In this tutorial i want to show you how easily you can display information about quantity of product that you've got in stock. After you apply proposed changes - your shop will display nice information about product's stock on category listing pages (and other pages where list of products appears)