I've never heard of TalkTo, but they sent me a press release announcing that they had created a page specifically for those searching for Wii Us, so I took a look . Turns out TalkTo is a system that allows you to search out businesses and send them texts. TalkTo then either emails or texts you the reply. For their Wii U page, Find a Wii U, they will give you a list of stores that carry the Wii U and allow you to text them and ask if they have any in stock.
I tried it out with a few nearby stores, and the technology worked but the answer was no at Kmart and Best Buy, and Gamestop not only was out of Wii Us for sale but couldn't even get their display model to work.
So you may not actually find a Wii U this way, but it's a nice system for searching.