Typically HTTP::Request is used in conjunction with LWP::UserAgent or various other modules. I don't believe this module actually performs the request.
See the UserAgent module for an example:
http://search.cpan.org/~gaas/libwww-...P/UserAgent.pm
Or LWP::Simple:
http://search.cpan.org/~gaas/libwww-.../LWP/Simple.pm
-r