I also have to 'fess up to making a really, really stupid mistake. I was working under the assumption that I had kernel 2.6 running but when I checked it, it was in fact 2.4.22-bf2.4.
Once that little bit of info came my way, I installed the source and headers and the nvidia driver compiled & installed without any hassle. I updated XF86Config-4 and that was it.
llamakc, eaglest, thanks for your help. If it wasn't for your advice, I'd probably have installed Whinedoze on this machine...