I'd meant to explore what was available on Open Library some time ago and got distracted, so let's try this again. Open Library is a resource for often-free books available online, sometimes as ebooks and sometimes through physical libraries (via WorldCat). Some of the writers available through free ebooks that I've found so far:
Unfortunately just because the listing has an ebook available doesn't mean it can always be downloaded. Some are protected by some service called Daisy which takes a special login. So it can be hit or miss, but any of those (and others--search bar top right) should give at least one selection that can be borrowed or read online.