I originally released my Tales of Space Exploration and Discovery exclusively through Amazon, but now the e-book version is available from a wide variety of booksellers.
Order from Smashwords: https://www.smashwords.com/books/view/1134741
Order from Amazon: https://www.amazon.com/dp/B09L59F9RZ
Order from DriveThruFiction: https://www.drivethrufiction.com/product/388306
More sellers will be carrying it in the days to come.
The paperback and hardcover versions are still available from Amazon.