I download lots of free books to my Kindle. All are good so far but they are part one books to get you to buy the next one.
Still prefer paper books and my favorites are the People books by Gear and O'Neal Gear. They are about North American Indians of the past. Since the authors are archaologists they have the facts to write fiction stories.
I read alot and have had to make a list of all my reads to keep track so I dont buy the same book again.
Also love the Lee Child books about Jack Reacher.