While some Linux distributions come with precompiled versions of Apache and mod_perl, it is almost always best to compile these programs on your own. That way, you are guaranteed to get the latest and greatest versions, set with the most appropriate options for your needs.
The source code for Apache is available at http://www.apache.org/ as well as many mirrors worldwide. Meanwhile, download mod_perl from CPAN, the Comprehensive Perl Archive Network, based at http://www.cpan.org/. Download and unpack the source code for Apache, but do not compile it directly. Rather, it is probably easiest to compile it via the mod_perl build process, using the “APACI” build process described in the INSTALL.apaci document that comes with mod_perl. When this build process is complete, the installed copy of Apache will include mod_perl.
Once Apache and mod_perl are installed, it will be possible to install Perl modules from CPAN that rely on mod_perl, including HTML::Mason. (Most such modules begin with the designation “Apache::”.)
The documentation that comes with Mason is extensive, well-written and available with either “perldoc” or “man”. The beginning Mason programmer will have to read both the HTML::Mason::Admin and the HTML::Mason::Devel pages to get a full understanding of the system; the former is aimed at site administrators, while the latter is meant for component developers.
Finally, the Mason home page is at http://www.masonhq.com/. It includes a list of publicly distributed components and documentation, along with information on the Mason mailing list.
All listings referred to in this article are available by anonymous download in the file ftp://ftp.ssc.com/pub/lj/listings/issue74/4002.tgz.