Here is the official site:
http://jakarta.apache.org/tomcat/index.html
You will find binary and source releases of all versions here, but no RPMs.
You can find RPMs for Tomcat 3.2 in the RedHat contrib (noarch) directories on your local RedHat FTP mirror (or here:
http://ftp.sunet.se/pub/os/Linux/dis.../noarch/noarch).
I have never installed Tomcat myself, and I haven't used RedHat in a couple of years now so I guess I'm not of big help when it comes to installing it.
hw