Many folks are already taking advantage of WordPress to sell products online. There are many exciting e-commerce themes and plugins available for this platform (such as WooCommerce and WP E-Commerce). You may not need a highly sophisticated e-commerce solution to start selling digital content online though. Take the Music Store plugin for instance. This cool script turns your site into an audio store you can sell your music, speeches, and other audio files through.
Music Store lets you sell your files via PayPal. You can sell single items or collections. The plugin is customizable and lets you filter products by types. The included audio player provides support for OGA, MP3., WAV, and WMA. Your files will be protected so you can stop unauthorized downloading audio files. A module to track sales statistics is available.
Music Store is not the most sophisticated e-commerce solution for WordPress but does enable you to sell audio through your site. It has potential.