It took some hunting down but I found it. Amazon.com's toll free number is: 800-201-7575. But think long and hard before you ever call. After dialing it today -- for the first time since I began buying books on Amazon ten plus years ago --  I now know why they keep it hidden. The help on the phone was pretty much incompetent.Nice, yes. Well intentioned. You bet. But a problem that should have taken two minutes to resolve took more than ten, and still I still didn't have my answer. I finally got so tired of the customer service rep putting me on hold, I hung up.I love Amazon. I'm amazed at how well their business runs from a user perspective. But next time I need help, I'll make sure to do whatever I need to to avoid human, um, help.