My wii has a inbulit antenna somewhere.... where do you find the antenna?

There isn't an antenna. There's a wireless Wi-Fi chip inside your Wii. I really do not recommend trying to find it. You can't increase the wireless range of your Wii, but there are some things you can try to prevent the signal falling short. Make sure there aren't any other devices around transmitting signals - phones, other consoles, etc, can interfere with the signal reducing it's range. Also make sure there are no solid objects between the Wii and your wireless router (or whatever it is you have), as there will block the signal somewhat.