Which desktop are you using (KDE or Gnome)
I'm gonna assume gnome as its the only one I'm used to.
Go to system>Administrator>Add/Remove software.
Now search for your wireless driver in that application.
The above will only work if you have a working Internet connection on the laptop.
So if you dont try below
So here is a good link to start with
http://support.3com.com/infodeli/too...uxdownload.htm.
Read the installation instructions on the site.
alternativly you could use a ndiswrapper to use a binary driver I dont know how to do that but a google search brings many guides.