A random book from my wishlist seems to be free on the UK Kindle store today:
https://www.amazon.co.uk/Forever-Fan.../dp/B07D8QTWJM
Forever Fantasy Online by Rachel Aaron and Travis Bach
This is self-published LitRPG. I don't know whether or not it's a good example, but Aaron has a good reputation both as a self-publisher (Nice Dragons Finish Last) and trad-publisher (Legend of Eli Monpress, Paradox mil-SF trilogy (as Rachel Bach)).