I have a couple of books published free and name your own price on Smashwords, but they do an annual sale where books are discounted for a month or free. You can look them up by category, but as authors have to apply, you may find new additions to the list daily. Log In
I have published books on Amazon Kindle and Amazon createspace. I knew smashwords ebook publishing platform before I knew about Amazon publishing platform. However, when I was ready to publish books, I chose Amazon. I chose Amazon because it is the largest online publisher and retailer.I have smashwords account, I will check your books. I may even land up buying few.
It's a good way to promote books for a month, and you can easily publish on Smashwords as well as Amazon. My books are on both platforms, but I don't market them heavily as they are more memoirs. The good thing about Smashwords is that you can offer coupons and promotions unlike Amazon, and it's good for SEO.