Kindle Cloud Help

[wide_worlds_joy]

Okay, i just got given a couple books for review by the author. Problem is that they are set up for Kindle, and I don't have one. It's stored at my "Kindle Cloud" storage site, and I'd really like to download them to my local PC in a format that Calibre can read, or, most preferably, a PDF file.

Anyone have instructions on how to do this?