Most of CPAN is marked as beta code, but this is from a reliable author and has been out for years. Apache::SessionManager also has a helpful author who shows up on the mod_perl list and answers questions.

Apache::AuthCookieURL is a good example of a module that does tracking without cookies. Apache::SessionManager solves most of the issues people normally have with using sessions, and is good for beginners who don't know what is already there and what they need to supply.