Hi,
If you use the activestate version of Perl, it comes with an object browser, using this you can see what is available.
For example, on selecting "Microsoft Excel 9.0 Object Library" in the main window, there are 2 lists populated with ole objects and functions available to the object.
As Corion said MSDN is the best place for info. The later versions of the Activestate Perl dev kit come with a vbscript convertor, which may be useful when converting examples from msdn.
Hope this helps.