Well, I'll fess up to the fact that I'm an idiot at this.
I can't find an executable. I ran "tar xvfz gcc-3.3.1.tar.gz" and it dumped all of the files into the /usr/bin/gcc-3.3.1/ directory, which includes a /gcc-3.3.1/gcc directory, but no gcc executable as far as I can tell.
I've added PATHS to both directories in the blind hope that I'm missing something, and when I run ./configure I still get
checking for gcc... no
checking for cc... no
configure: error: no acceptable cc found in $PATH
This may not be something you can tell, but am I missing some key files? There's a ton of files in the /usr/bin/gcc-3.3.1. and /usr/bin/gcc-3.3.1/gcc, but no gcc executable as far as I can tell.