basic excel training - Pivot tables

I have Microsoft Excel 2003 and on this version you don't appear to be able to draw formulas from a pivot table - i.e. when you create a pivot table you can't draw the data from the pivot table into formulas. The only way I can seem to use / manipulate the data in a pivot table is to copy the pivot table using paste "values" and working from this copy - the problem is everytime you need to update the pivot table you also need to recreate the usable version. Is there a way to use / manipluate the information in a pivot table without having to create a new version by pasting values?

I hope this makes sense!

Cheers
NICK