For plain GET calls, you can use LWP::Simple (if you dont need any specific referer, or cookie stuff)

#!/usr/bin/perl -w
use strict;
use LWP::Simple;
my $result = get(http://www.perlmonks.com/index.pl?node_id=131");
[download]

With POST you'll need

#!/usr/bin/perl -w
use strict;
use LWP::UserAgent;
use URI::URL;

my $WWWAgent = new LWP::UserAgent();
my $url=new URI::URL 'http://www.perlmonks.org/index.pl';
$url->query_form(node_id => "131");
my $WWWRequest = new HTTP::Request 'POST', $url->as_string() ;
my $WWWResult = $WWWAgent->request($WWWRequest);
die "Error logging in $WWWResult->code $WWWResult->message" if(!$WWWRe
+sult->is_success);
print $WWWResult->content;
[download]

Greetz
Beatnik
... Quidquid perl dictum sit, altum viditur.