If you have access to another PC with internet, and you have a flash drive of some sort, you can just download the latest drivers and software for your linksys wireless card from [url]http://www.linksys.com[/url].  

Copy the file you downloaded to your flash drive, and bring it to the computer with the linksys card, plug in unzip/open the file and run setup if it doesn't already do it for you.