Toad Away - Gleitzman, Morris

Limpy is fed up of seeing his relatives run over and when he hears of a place in the Amazon, where human and toad live together in harmony, he resolves to find this place for himself and to take his cousin Goliath with him. The two toads make their bumpy way to the Amazonian jungle. But the jungle is not the Utopia that Limpy had imagined.