It’s not easy to find and certainly not published, but Amazon.com actually has a direct customer service phone number that you can call to resolve issues with an order. That customer service phone number is: 1-800-201-7575.
You can also use Amazon.com’s call-back request form, but I’ve never tried it and I don’t know how quickly they call you back. I called the number above and was talking with a person about my order in less than 1 minute.
UPDATE: A new # to use: 1-866-216-1072