complicated formula help
 

I'm trying to create a formula that will automatically copy results from
multiple pages onto same work sheet. the idea is that all results from all
pages entered will appear on a master page.
the problem is that although on different pages, the cell numbers can be the
same.
Q is there a way of when a cell is being used as a result from e.g. page 3
cell a2 which should be displayed on page 1 cell a2 would automatically drop
to say e.g.page 1 cell a3, because page 1 cell a2 already has input from the
result on page 2 cell a2

thanks fro any help you can provide