quotemeta or \Q..\E will fix your problem with special characters if you want to use a regex. Should probably add some boundary requirements though as well: 
foreach $line (@list_of_files){
    if ($line =~ /^\Q$find_file\E\s/){
        print ($line);
    }
}

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In reply to Re: Using a Variable as a Match Expression by wind
in thread Using a Variable as a Match Expression by Anonymous Monk

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