Slight flaw in that logic. Windows can not download the driver for their usb Ethernet dongle if they are not online, and to be online the usb dongle's drivers would have to already be installed. A bit of a Pandora box
W8 is pretty good about having the drivers for a lot of random hardware. If your usb adaptor's drivers aren't already on windows it would be pretty easy to go to a McDonald's or any other place that has free WiFi and use it to dl the drivers while grabbing a snack.
or Newegg would be a good place to check. Find the one that is cheap and has a ton of positive reviews.