Another place you can sell your digital content through is payloadz.com.  They interface with PayPal, Google Checkout and eBay, and provide the add to cart and checkout button codes for you to use on your website.

 This is a good solution for people who don't have the time or experience for setting up a cart system on their sites or who cannot get SSL certificates for their site.

 I have been selling a product this way for over a year and have had no issues with the service.