ethernet, usb dsl modem, two pc’s

I have recently networked 2 pc’s. I have since subscribed to a dsl service. the provider sent a usb dsl modem. one machine now blazes down the information superhighway while the other one is asleep in the weeds. any suggestions on configuring for this topology would be grately appriciated.
Cliff
mrcaland@bellsouth.net