ACCESS TO PROTECTED DOCUMENTS
       Documents protected by basic authorization can easily be
       accessed like this:

         use LWP::UserAgent;
         $ua = LWP::UserAgent->new;
         $req = HTTP::Request->new(GET => 'http://www.linpro.no/secret
+/');
         $req->authorization_basic('aas', 'mypassword');
         print $ua->request($req)->as_string;

       The other alternative is to provide a subclass of
       LWP::UserAgent that overrides the get_basic_credentials()
       method. Study the lwp-request program for an example of
       this.
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-- Randal L. Schwartz, Perl hacker

It may not be relevant..... but you scare me ;)

I've also dealt with some sites where authtentication is just a form. For example, this was enough to get me into one:

use HTTP::Request::Common;

my ($user, $password);  # Set to whatever ...
my $request = POST("http://www.whatever", 
                   Content => [ UserID => $user,
                                Password => $password,
                              ]);

# Feed the request to LWP::UserAgent, etc.
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