I haven't done it myself, but the Win32::Ole documentation
looks quite simple (simple of course, if you know the Excel
"object model")...
The MSDN has some documentation on the Excel object
model, as has the Office Development Kit, something you
might want to buy if you do Office development on a regular
basis...
Some code from the top of my head - I haven't done
Excel automation for a looong time ... Note that you can
take the method and object names from any VB code, as both
Perl and VB call through the IDispatch methods of Excel.
$ex = Win32::OLE->new('Excel.Application') or die "oops\n";
$ex->Worksheets(0)->Cells(0,0) = "Hello world";
I'm not sure about the parameters you have to pass to the
Cells function - some VB sample code should be
easy to port though.