Hello! As far as I know, the most popular platform for the e-store is Magento. I use ready-made templates from http://www.*********.com/designs for making websites. I use Magento in all my online projects, I like this system. It's main strength is the abundance of built-in functions: it's about currency, languages, discounts and coupons, reports and much more. In addition to the built-in functionality, Magento has many modules (or extensions) and various templates. Also, do not forget that it is a scalable and extensible platform.