I think WMWifiRouter is working on a version that works with the Wii. Currently, the only game console it works with is the Xbox360.
http://support.wmwifirouter.com/devices/
You could tether the touch to a laptop (or PC if its close to the Wii), then use internet sharing via ethernet cable to get it to work. I have actually done this with my 360 before. You would also need the USB ethernet dongle for the Wii, since it doesnt have a built in ethernet port.
As far as tethering it directly to the Wii...I doubt that will ever happen....Nintendo would need to release some sort of driver or firmware upgrade for that to happen.