Well, this is a topic near-and-dear to my wallet. I use Amazon ADs, and FB, and Google, and Taboola, for my new releases and the results have been less than stellar. However, what's life without self-inflicted punishment?
Focusing on Amazon, my latest effort is seeing improved results for what I think are these reasons:
1) My following is growing. Across all platforms I have a few thousand followers. Amazon/Kindle followers improve new release visibility.
2) Spending more per-click for pre-sales ADs. The eBook doesn't drop until the 27th, but I have already had several paperback sales. (Still a negative ROI)
3) I am pushing the book at a pre-order discount.
This effort has more pre-orders than all my prior pre-sales efforts combined.
Conclusion: If you have enough follower mass, and money for clicks, Amazon ADs for new release can be successful.
R.C.
The book:
Tule Fog