By Monk Ashland (pseudonym for Chris Rettstatt) & Nigel Ashland. 2008. Hardcover. Based on the Kaimira world, characters, and storyverse created by Chris Rettstatt. Illustrated by Jeff Nentrup.
The book was the first of a planned series Kaimira, but on 11 March 2017, Rettstatt made a post on his blog confirming that no further books will be written in the series due to intellectual property issues.*
“In a future where wild beasts, humans, and mechanical beings battle for control, two children, on opposite sides of the Earth, connect through a mysterious journal that comes alive to reveal a powerful primal force and frightening destiny.”
*from the Wikipedia article.