Wow, so this is the first time I've seen one-click purchasing (It's not normally enabled for me). It's really disconcerting. Not that I want to (and it's only $3) but is there any way to cancel a one-click purchase? It's not obvious..
> Books you purchase from the Kindle Store are eligible for return and refund if we receive your request within seven days of the date of purchase. Once a refund is issued, you'll no longer have access to the book. To request a refund and return, visit Manage Your Kindle, click the actions tab for the title you'd like to return, and select "Return for refund."
