Mairelon the Magician (Mairelon #1)
Kim doesn't hesitate when a stranger offers her a small fortune to break into the travelling magician's wagon in search of a silver bowl. Kim isn't above a bit of breaking-and-entering. Having grown up a waif in the dirty streets of London-disguised as a boy!-has schooled her in one hard lesson: steal from them before they steal from you. 

But there is something odd about this magician. He isn't like the other hucksters and swindlers that Kim is used to. When he catches her in the act, Kim thinks she's done for.
Until he suggests she become his apprentice. Kim wonders how tough it could be faking a bit of hocus pocus.

But Mairelon isn't an act. His magic is real.
Fiction, Fantasy, Magicians, Magic, American Science fiction
Patricia C. Wrede
Patricia Collins Wrede (born March 27, 1953) is an American author of fantasy literature. She is known for her Enchanted Forest Chronicles series for young adults, which was voted number 84 in NPR's 100 Best-Ever Teen Novels list.