Yeah...sorry. I meant to elaborate a little more. That's what I get for talking to my wife and trying to answer a question.
What I meant to say is that provided that your NIC is recognized, all you should need to do is run the network configuration tool. You can open a terminal window or virtual console and type in the command
and it will bring up a dialog box that will allow you to enter your network settings.
Since you are running RH, you might go to http://hardware.redhat.com/hcl/
and do a search for your NIC. If it is supported, it will be listed there. If it's not, that means that the road ahead could be long, dark, and lonely. Next, check on D-Link's site, (in fact, go ahead and check there because your particular NIC isn't on the RedHat site).
If you find some support on D-Link's site, read the README file completely. I hope all this helps, and good luck. I'm sure there are some others that check this board that can give you more detailed help.