A Farm Boy in Oz - The Wicked Wizard of Oz, #1

WARNING: Be advised, this version of Wizard of Oz contains strong language. For the last three years, Dylan Gale has been his dying mother's caregiver. When he's not taking care of her, he single-handedly tends to the family farm. Well... not quite single-handedly. He gets a lot of help from his loyal terrier, Simon. One night, a storm sweeps through Kansas and whisks him away to the land of Oz. There, he meets a "good" witch named Glennis, who sends him on an important mission to save the people of Oz.
He's actually murdering her sister, but he doesn't need to know that. Along the way, he meets a foul-mouthed lady scarecrow, a cowardly knight (wearing way too much armor), and an excessively polite robot named Ten. A Farm Boy in Oz is a genderbent fantasy retelling that isn't meant to be taken too seriously.