Walmart offers Alice Schertle and Jill McElmurry's Little Blue Truck Leads the Way Board Book for $3.86. (Amazon charges the same with free shipping via Prime.) Opt for in-store pickup to avoid a $5.99 shipping fee. That's the lowest price we could find by $5.

Also available is the Little Blue Truck Board Book for $4 with in-store pickup. (Amazon charges the same with free Prime shipping.) That's a low by $5.