Start with high-confidence transportation books, then narrow by subgenre or adjacent topics.
Door to Door
Edward Humes
Shifting Gears
Susan Handy
What Do Wheels Do All Day?/¿qué Hacen Las Ruedas Todo El Día? Board Book
April Jones Prince
Amazing Machines: Shiny Snow Machines
Tony Mitton
Transportation!
Gail Gibbons
Modelling Transport
Juan de Dios Ortúzar, Luis G. Willumsen
Principles of Highway Engineering and Traffic Analysis
Fred L. Mannering, Scott S. Washburn
The Fast and the Furious
Helen Wells
Inclusive Transportation
Veronica Davis, tamika l. butler
Ambulances
Kate Riggs
The Future of Transportation
Atossa Araxia Abrahamian, Darren Andersen
An Introduction to Traffic Flow Theory
Lily Elefteriadou