Del Rey. They currently have the entire run in five graphic novels.
Vol. #2 starts out with Kakashi and Dorothy being rescued by the now magically-transformed Toto who has turned into a large dragon-like beast. Toto then merges with Kakashi's left hand, and he now wears the dog bracelet of which Toto's can emerge from in his monster form. He can also eat anything inorganic and reproduce it again like a canon or shield(sorta like Eat-Man). Lt. Vio and is troops are totally overwhelmed by Kakashi's newfound powers, but the sinister Corporal Chopin arrives seemingly to give them backup. He instead uses his own special abilities to kill Vio for his failure. Chopin leaves since he didn't have order to get the collar, and Vio relays Kakashi what he knows about the collar. Its one of twelve accessories that each have their own power, and whichever country can gain the most of them will rule over the rest. Kakashi and Dorothy make their way to Dego City which is a central junction for railroads, althought the Nassau army is tearing down the trains to use for military salvage. Kakashi nearly gets in trouble with some officers, but is rescued Millicia, a local bar owner who claims he's her brother. They then meet Noil, a flaky officer who runs the scrapyard and is a struggling comedian/magician who suffers from stage fright. He takes Kakashi on as his apprentice since he thinks his dog-hand is a magic trick. The military eventually find out Kakashi has the collar, and capture Dorothy to lure him out. Things look bad until a small train engine busts out of Noil's shack.
Vol. 3 opens with the train being run by Noil, that he made it on his own in the scrapyard to one day skip town. He rescues Kakashi and Dorothy as they go down the line called the Yellow Brick Road. They travel through an area called the Witch Forest, and actually encounter a young witch flying in on a broom. She is Paisley, a "good witch", and part of an originization called World Institute of the Twelve Creators' Heritage(or "WITCH" for short)whose main purpose is to locate all the magical accessories. Then the Nassau army shows up with Chopin to collect the collar. Chopin himself has some special rings which are some the accessories(whether they count as seperate accessories or a single one isn't mentioned)which spring out as snakes that turn people to stone. Nassau defeats him, but Noil's train is destroyed by Red, another WITCH agent guarding Paisley. Our heroes head to the local WITCH headquarters where they discover that the one who unintentionally released the accessories out into the world in the first place was Kakashi's father, Nick Q. Kakashi realizes that in order to find his missing father, he must become an agent of WITCH and search for the remaining accessories. In order to join of WITCH, Dorothy must finish her martial arts training to be his partner. She goes to study under the karate master, Kenbi Sow. Kakashi later reveals that Kenbi secretly uses one of the mystical accessories, and team up with one his students to expose this. However, this student is really Major Damda with the Nassau army.
I like how the story is progressing so far. Yuko Osada's style develops as the series goes along. It seems like its one of those shonen titles like Dragonball which hinges on a quest for several magical items, although it doesn't appear they need to find all twelve of the accessories, because that would make for a much longer series.