maybe find some in the magazine or a newspaper for ads at malls, or children's homes, if you do it at children's homes, you'll get that fuzzy feeling of happiness, but if you do it at malls, you get paid more
good luck getting a job as a santa, i reckon they would advertise in the paper or the net.
david sedaris wrote a really hilarious book called the santaland diaries, where he spent his holidays as a college student working as one of santa's elves in a shopping mall. its a great read, it may give you inspiration, or an insight into the industry. haha, good luck!