How would you publish a book and sell it on Amazon? It turns out Amazon owns CreateSpace.com who make books on demand whenever a customer clicks - so it costs nothing. They then deliver it (with "free super saver shipping" and gift wrapping options). You calculate how much to charge based on the profit you want - eg. $10 per book could work. For the Kindle, you'll make 70% from $2.99 to $9.99 (or 35% on cheaper titles). You can upload a Word doc. And CreateSpace does the same for the CDs and DVDs you've been producing. Here's a video overview which won't work on Apple devices (3m30s).
(via The Altucher Confidential)