Connect to the internet with a cable.
Use the ubuntuforums, here, and google.com to search.
You will need to type
to see which interface is active.
Code:
dmesg | grep ethX <X being the non active NIC>
ifconfig ethX up
iwconfig ethX essid any
You also will need to look at the specs to be able see which wireless driver you need.
Have you installed wireless tools?