This is my question, too.
I might be wrong, but I think you're supposed to use some sort of converter cables to be able to use it in North America (because you have to connect it to the TV using AV cables). If not, then you just need the AV cables to connect ito the TV and the power cable, of course.
Here's what AV cables look like:
One side connects to the back of the system and the other to the TV so that the TV receives the video signal.
If you didn't get any AV cables when you bought the system, then you need to buy them. They're not too expensive, and this is the only way to connect the N64 to your TV.
Also, once you've got it connected to the TV using those red, yellow and white cables, you should try using the input button on your remote (while the N64 is on) and switch through the input channels to see which channel works.
So, here's what you need: