Go via control panel to Network connections - you should see a wireless icon - probably with a red cross on it.
Right click on the icon and view available networks.
Then connect to your router...
Be sure that the drive you have matches both the operating system and the wireless device hardware.
The wireless card in your machine may be able to "see" several wireless routers but will not know which one you wish to use - you need to tell it.
Peccavi
January 2011