Try this...

#!/usr/bin/perl

use strict;

while (<DATA>) {
    my $line;
    ($line) = $_ =~ m|\w+.*\s(http://\w+.*\.html\s)\w+.*|;
    print "$line\n";
}

__DATA__
This is a test this is a test test test http://www.website.com/getme.h
+tml this is test this is a test
This is a test this is a test test test http://www.website2.com/getme.
+html this is test this is a test
This is a test this is a test test test http://www.website3.com/getme.
+html this is test this is a test
This is a test this is a test test test http://www.website4.com/getme.
+html this is test this is a test
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