There was a driver posted a while ago, but MS asked the provider to remove them, you might be able to still locate it though. The driver was for those that used ASX Chipset (which is most on the market).
I just tried my already old Nyko NetConnect USB to Ethernet that I use for my Wii. Installing the drivers that were posted somewhere else this actually works.
Nyko NetConnect item#87024-E14. If I have some time I will post a picture of it. I think I bought this at Newegg or Amazon for ~$10.
the drivers to look for are AX88772B_772A_772_WinRT_Driver_v220.127.116.117