How do you make someone in your town move into a friend's town in Animal Crossing Wild World?

There isn't really a certain way to do that, but there is a method. First, make the neighbor you want gone angry by hitting him/her with a shovel or net, or being rude to them. When he/she talks to you about moving away, tell him/her to go away. Then, have one of your friends come over to your town after you've told your neighbor to go away. Soon, your unwanted neighbor will move away, probably to your friend's town. This only works if there are less than 8 people in the friend's town.