oh...i think i get you....you don't even need perl for that (although you easily could)....On any decent machine (unix/linux or a windows machine with cygwin installed)

grep "Joe's Store" your_filename | wc
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..or in perl:

while($line=<>) {
  chomp $line;
  $a++ if($line =~ /Joe's Store/);
}
print "Joe's Store occured $a times\n";
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