>The easiest route for non-Amazon formats would be to download the ebook, import it into calibre, convert it to a Amazon format either mobi or azw3 and then use a USB connection to send it to your Paperwhite.
Thanks. That would be my current method. Could some of these steps be automated with a shell/batch script? I did a search and found that Calibre has a good commandline interface:
Calibre commandline
Has anyone used those?