These days, it is not enough to have a single eCommerce store. To keep up with the competition, eCommerce entrepreneurs must promote their products on several online marketplaces that attract millions of customers and allow retailers to expose their brand and sell directly to shoppers who may not otherwise know about their store. With scores of products, million-dollar marketing and ranking prowess, marketplaces like Amazon, eBay, Buy.com, Sears and others garner more shoppers than an online store.