First, look in the yellow pages for dance studios. Then, I have three plans for you:
1) Sign up for lessons. They'll tell you where to get tap shoes, and they'll also teach you to dance, but they'll want you to pay them, like, money....
B) They might be willing to give you a free trial lesson, especially if you give them the impression you have vast amounts of money to be bilked of. Wear a lot of cubic zirconias when you go in to ask. Um ... no, maybe better not wear a lot of cubic zirconias -- then they would tell you the most expensive place in town to get tap shoes.
III) Just get the address from the yellow pages -- don't call them. (They might be able to trace the call.) Dress in your black ninja outfit and tiptoe over there and lurk outside the door at the end of a dance class so you can ask the students where to get tap shoes.