There are lots of cheats out there that give you large amounts (or unlimited) Bells, but they will come with side-effects, like bug invasions. The easiest and fairest way to get money is to earn it - pick up anything you can find, and sell, sell, sell! Things like fossils and rare fish/bugs are worth a lot of cash.
[Edited by xxjjrockerxx, 7/20/2008 11:36:03 AM]
i have action replay and i dont have any side effects