They are scattered on rooftops and you can also find them in the play house (the building with the slides and ball pit) if you go in, get the coin, walk out and then repeat the process.
to find coins
in the fun house
Catch them!
you go find a token and spend it on Fast Ball Fury
you need to find the ladys son after getting another guy unstuck from the slide
Get the metal detector from the man. The keys are near the lady's blanket.
He is hiding in the ball pit at the fun house. You don't find him until later in the island, though.
You have to go to the Fun House and look all over and you'll find the ones you need to get the jumbo prize.
You'll find Rowley stuck in the slide in the Fun House. Use the suntan lotion to get him out.
He is deep in the ball pit.
beach
you have to find the key