Needed:

The island
5,000+ simoleans

1) Go to the island at night.
2) Go into the casino and buy as many tokens as possible.
3) Play Tic Tac Trump, betting 10 tokens and doubling it each time.
4) At some point, you should be able to bet 30 and 50 tokens if you play a lot. This will help you accumulate tokens.
5) After you have 10,000 tokens, go to the token machine and exchange your tokens for a video game company.

I don't know what it does, because I only have 7635 tokens.

I don't know if anyone has noticed but as you walk around the different places you can find hidden objects or money. They are easier to find at night. You have to look for a little sparkly spot on the ground. Walk around slowly though because you can miss them. I usually find them in the port area, highlands and mountains. Once you find one walk over the spot and tap. It may take several attempts. If you remember where they are you can go back night after night collecting everything. Good luck.

OK, some people might already know this, but I'm putting it anyway. Before you try to cheer up someone or do a mini game, save. Then, play the game or attempt to cheer up someone. If it doesn't go how you wanted it to go, turn off you DS WITHOUT SAVING. Turn it back on, load, and you'll see that it's like you never even did that.
(I have tested it, and it works)

If you don't know what to do to fill up the fourth star and you are all ready half there then try talking to Helen(Town mayor) and she will tell you something about putting up a town symbol, you have to choose a head and a body for the statue which can be obtained when you have the dowsing minigame by exchanging points for prizes.

To do dowsing just keep clicking on the red spot and you will eventuly get it also buy a head and a body and then go to the mayer and you will then have do go to the rock that says ''something big can fit on here'' or something (its in the town) and your head and body will become the town statue! HAPPY GAMEING