If you get a Wii U, you must connect it to the internet. The day-one system update enables a lot of important features, like Miiverse, Wii U Chat, eShop – none of which would do you any good without internet access anyway – and even Wii backward compatibility. If that effort is hampered by inability to connect with your router, you are not alone.
Nintendo tech forum user GAMEDEV posted a guide to manually connecting your Wii U to wi-fi. We've reproduced it after the break. We hope you're able to get online and start "Yeah!"-ing your friends' Miiverse posts immediately.