Where would you find your locus magicalicus?

Okay, I had a hard time putting down The Magic Thief by Sarah Prineas! If you like the whole wizard/apprentice/magic thing, this is the book for you. Conn is a pickpocket, and one day he steals the locus magicalicus of Nevery, a very powerful wizard in the town of Wellmet. Touching the locus should've killed Conn, but it since it didn't, a surprised Nevery takes in Conn, first as a servant and later as an apprentice. Conn is soon looking for his own locus, while trying to help Nevery figure out why the magic in Wellmet seems to be dwindling away. Of course there's the "bad guy" element, and late in the book, you'll probably wonder how in the world Conn will get out of the situation he's in. The ending is satisfying, but there's enough of a teaser for you to figure out there must be part of a series...and it is.