Perhaps you already knew this, but I just realized it today when I opened my "Create Space" account that shows the recent sales, etc. of my book through Amazon. Amazon will now convert your print-on-demand book into Kindle format for 69.00. They send you the files, including your cover properly formatted and then you upload it yourself to Kindle's site.
I do not think this service has been available very long since I looked for it a few month's ago. Anyway, good news if you already have a book ot two listed with Amazon. I sent a request inquiring about whether or not this format will work for Smashwords and the other e - book compilers. I will let you know when I hear back.