My Kindle for Mac (free app) seems to have no kindle email address associated with it. It appears as a device in Amazon under “Manage Your Kindle” – “Manage Your Devices”, but without an email address. I tried using the first part of my Amazon login email with the ending of @free.kindle.com, but that didn’t work. That is, Push to Kindle sent it, but I received nothing.
Yes, this is unfortunately something Amazon does not yet support. Their web page states: “Periodicals such as newspapers, magazines, and blogs, and personal documents cannot be viewed on Kindle for Mac.”
Our service relies on personal documents support.