Oh, wait. You have to be connected to the internet to download the wireless router drivers so that you can connect to the internet.
I went to the old computer, downloaded the Vista drivers for the adapter (most recent version Linksys had on their website,) and put it on the USB drive. Nope, Windows 8 doesn't even recognize that .sys file as being a driver. Hell, it was pretty hard to figure out just how to manually add drivers instead of relying on it checking the non-existent internet.
So I went to the Tom's Hardware website or whatever it's called, downloaded the program that supposedly will install drivers for that wireless adapter... oh, it doesn't actually include the drivers, either; it wants to connect to the internet. Useless piece of shit.
So I caved in and moved the new computer. Downloaded the driver for the wireless and a couple other things I needed to install, let it do its update. At one point, Windows told me it had an update it wanted to install, I told it "I will do it later". Thirty minutes later, Windows says "fuck you, I'm doing it RITE NOW, IYKWIM."
Eventually, I moved the computer back to the less-crowded location, connected it to the wireless network, and now I'm finishing setting it up. I figure I won't actually move it back until (a) I'm sure all the stuff I want on the old computer is copied over, since it's going in storage; and, (2) the cables and thumb drives I ordered arrive, so I can set it up properly and have a recovery thumb drive ready.