Assuming you are booting into RH 2.4.18-XX.XX kernel. You can get the kernel source from the Redhat site. OR you can use the RH udate utility to update the kernel AND download the source files at the same time. I notice that you are running RH7.3.! Are you booting into that kernel when you try to compile the Nvidia Drivers??
As shown from you list, you need to download the 'kernel-source-2.4.18-24.7.x.i386.rpm' file. And install that before you compile the Nvidia drivers.