Wireless Network Not Working

Inspirion 6000, Windows XP. Installed Belkin Router but not connecting with laptop. On phone with Belkin and we went thru all the settings.  His conclusion is the network card needs a download.   Where do I go to get it. I couldn't find a clear cut download for this.  I have spent hours trying to find out what the problem is. Please help. School will be starting and I need the lap top to wifi for homework. It has connected to other locations in the past!  I've never had any problems before connecting anywhere else!