USA link:Books Inc, an independent San Francisco based bookstore is a great place to pre-order.

https://www.booksinc.net/book/9780316492508

Also Amazon is fine

https://www.amazon.com/Puzzle-Solver.../dp/0316492507

Canada link:https://www.amazon.ca/Puzzle-Solver.../dp/0316492507

https://www.chapters.indigo.ca/.../9780316492508-item.html

UK link:https://www.waterstones.com/.../tracie-white/9781911630616

Australia link:https://www.dymocks.com.au/.../the-puzzle-solver-by...

https://www.booktopia.com.au/the.../book/9781760875695.html

https://www.hachettebooks.com/.../the.../9781549177545/

https://www.amazon.com.au/Puzzle-Solver.../dp/B08KRHLX79

EU link:https://www.amazon.com/Puzzle-Solver.../dp/0316492507

How to buy products on Amazon from European countries:

https://borderoo.com/.../how-to-get-amazon-shipped-to.../

If this doesn’t work, Waterstones in the UK ships internationally. But it would be better to pre-order “The Puzzle Solver” version from Amazon or elsewhere if you can.

https://www.waterstones.com/.../tracie-white/9781911630616

The Netherlands link:https://www.bol.com/nl/p/the-puzzle-solver/9300000002148511/

India link:https://www.amazon.in/Waiting-Superman.../dp/B08G6FM7S6