Welcome Jane, and welcome to the forums.
If you're looking for free kindle books, I can think of three or four places that you can readily download free titles.
Manybooks.net and
feedbooks.com cover mostly books that have entered the public domain, and books that have been licensed under creative commons. Baen Books'
webscription.net also maintains a free library - mostly books that they'll sell you sequels too. You can also find titles that are out of copyright here under the 'books' pulldown menu at the top. I'm sure there are some that I'm forgetting, but those should make for a good start.