I suggest using this release, which is not the newest but supports your hardware, and which I know installs on RH9 smoothly. Be sure to read the text readme from this page covering most of the issues people have while installing. You may need to install the kernel-source package for your kernel before using this driver. Download the .run file and follow install instructions in the readme.
Here is the newest driver release that will also work with your hardware, but I haven't personally used it on RH9 (tho I'm running this one on my system).