check if you can ping an IP (64.179.4.149 aka
www.linuxquestions.org for instance).
If not, you're problem is elsewhere.
Check all relevant settings with redhat-config-network (it's on the RH9 cd's if you didn't install it).
HTH,
Sven
[PS, edit]: Do you run your own DNS server? If not, call your ISP to ask for the IP's of the
nameservers if you don't already know them.