List of free nonfiction Kindle books, updated daily
nonfiction.fkb.meAmazon affiliate links.
Aren't those free ebooks easy enough to find directly on Amazon?
Do affiliate links bring any money if they lead to free content? Actual question. Does not make much sense if they do.
Not if you buy the free book, but you might end up buying another book instead (e.g. from recommendations). One still gets a (smaller) cut if the customer buys anything else within the current session.