how to get ethernet controller device installed

I had a new hard drive installed and I reinstalled Windows XP from the CD. 

 

 I can't connect to the internet. My ISP told me I need to install the drivers and utlities to get the ethernet controller (under device manager).  Well, I have a "Dell Dimension and Dell XPS ResourceCD" and I've reinstalled the Dell System Software but I still am not showing under the device manager, under Other Devices, that the Ethernet Controller is correct.

 

Dell only sent me a new Windows XP CD to reinstall.  Could I be missing another Drivers and Utilities disk?  Not sure how many there are to reinstall.

 

thanks!