WooCommerce is the most popular e-commerce plugin for WordPress. Now you can have a shop with all e-commerce features on WordPress.
Before you start adding products, please go through the WooCommerce plugin settings and specify everything you need for your shop:
Adding the products: You can easily add new products via Products > Add Product
Just specify all details with the description and shipping details. For a single product, you can upload several photos in Product Gallery. More information about the WooCommerce features you can find here: http://docs.woothemes.com/documentation/plugins/woocommerce/getting-started/