Folks, I've posted a couple Free (at the time of posting) Kindle books but the ones that I post are of interest to me. I get them from HOMESTEAD SURVIVAL - the site author posts them every day. They run the gamut from romance novels to 2A books to apocalypse novels to prepping tips, the choices vary from day to day but rarely a day goes by that I don't download something from there.
If you happen to miss a day, go to the sidebar and you'll see a drop down menu. Click on that and you'll see the category.
Also, at the end of each day's free books, she has the links to convert Kindle books to Nook & Sony as well as your PC if you want to turn your friends onto it.