This is not my hat: https://www.amazon.co.uk/This-Not-Hat-Jon-Klassen/dp/1406353...
Black dog: https://www.amazon.co.uk/Black-Dog-Levi-Pinfold/dp/184877052...
FArTHER: https://www.amazon.co.uk/FArTHER-Grahame-Baker-Smith/dp/1848... (Sadly this book uses a stupid font. Other than that it's lovely.)
Pirate Diary: https://www.amazon.co.uk/Pirate-Diary-Journal-Jake-Carpenter...
I get these from the CILIP Kate Greenaway award. Once you know the name of the writer, or illustrator, or even publisher, you can usually find more good books. http://www.carnegiegreenaway.org.uk/greenaway.php
CILIP is a UK librarian organisation. The US equivalent award is probably something like the Caldecott Medal: http://www.ala.org/alsc/awardsgrants/bookmedia/caldecottmeda...
Pirate Diary - The Journal of Jake Carpenter by Richard Platt, illustrated by Chris Riddel. (I think this is good. The illustration is very good (and it won a Greenaway medal for the illustration).
https://www.amazon.co.uk/Pirate-Diary-Journal-Jake-Carpenter...
A Flat Stanley collection. (I don't think it's much good. My son enjoys it though.)
https://www.amazon.co.uk/Flat-Stanley-Collection-Jeff-Brown/...
And I'm about to start re-reading everything by Fred Vargas.
https://www.amazon.co.uk/Fred-Vargas/e/B001I9OXT6/ref=sr_ntt...