Easy Digital Downloads is a pretty popular plugin in the WordPress community. Many folks have used it to sell digital products online. It supports multiple payment gateways and has many extensions available for it. If you plan on adopting this plugin to start selling your own digital products online, you should check these Easy Digital Downloads themes out:
ReStored: has everything you need to start selling digital products online. It is ready to be localized and has multiple color options. The jQuery slider and hover effects are decent.
Webbie: a beautiful theme for e-book authors. Use it to promote the books you are selling online or offer them directly through your own site.
CrowdPress: this theme is powered by Easy Digital Downloads and Astoundify’s Crowdfunding plugin. It is responsive and has some useful custom widgets.
Thrifty: Thrifty is compatible with Shopp, Easy Digital Downloads & WooCommerce. It has a pretty clean design.
Campaignify: yet another crowd funding theme. It has 11 custom widgets and multiple page templates. The theme is ready for retina displays.
Digital Store: an official theme for Easy Digital Downloads. It is a simple theme with light & dark color schemes and custom background support.
Shop Front: a lightweight and simple design for this plugin. It is responsive and has a logo uploader, 6 widget areas, and custom page templates.
Themeshop: an experimental theme for selling digital downloads online. It is compatible with Easy Digital Downloads. As the name suggests, you may want to use this to sell WordPress themes online.
You don’t have to use the above themes to get EDD working right on your website. But these templates do save you time if you need to take your digital store online fast.