Kindle e-book Formatting Q?

I guess I'm not really sure about what you are asking but will say that you can take any free publication without DRM and use Calibre, as Robert78121 said, to convert it to Mobi(pocket) file format. Then you use your PC to drag the Mobi file to "documents" under Kindle.

If you buy the book from Amazon it will download to everyone on your account without any conversion.