Oneitis
ahh thats never good. i was having this problem the other day
my best advice is this:
so when you're on the settings screen
make sure you write down the hardware/model/serial number of the driver you need
and then when you have access to a computer with internet
download the corresponding ethernet driver from the internet to a flash drive
then take that back to the computer youre having trouble with
install those drivers from the stick, boom, done. 4laugh
im on the computer as we speak, just on one of those wifi usb thingies, problem is that wifi wavers constantly