The Boneyard by Seanan McGuire is the third installment of the Deadlands series of books from Tor publishing. The others being Ghostwalkers by Jonathan Maberry and Thunder Moon Rising by Jeffrey J. Mariotte
Here is the link to more on the book. The Boneyard
I've included the sketches. We changed directions after the first round of sketches to better reflect the Circus setting of the book. It definitely fits the book better, even though I liked the original sketches.