If you have some code you're working on could you post what you have so far?

If not, are you aware of the Excel spreadsheet modules from the CPAN? Have a look at Spreadsheet::ParseExcel::Simple, from the synopsis:

my $xls = Spreadsheet::ParseExcel::Simple->read('spreadsheet.xls');
foreach my $sheet ($xls->sheets) {
   while ($sheet->has_data) {  
       my @data = $sheet->next_row;
   }
}
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and Spreadsheet::WriteExcel::Simple, again from the synopsis:

my $ss = Spreadsheet::WriteExcel::Simple->new;
   $ss->write_bold_row(\@headings);
   $ss->write_row(\@data);

print $ss->data;
      # or
      $ss->save("filename.xls");
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That should get you started anyway, once you get it working if you need more complex processing use Spreadsheet::WriteExcel and Spreadsheet::ReadExcel and post some code detailing where you are stuck.

Hope that helps.