How to report changes in a spreadsheet (not track changes)
 

Hi folks,

I have a spreadsheet with say products and their ID's and a column
with no. of customers who have purchased that product. This sheet changes
quite often and I was wondering if there's a way to say create a report of
all the changes (in a separate sheet if possible)
Now, the number of customers for each product could change, but also there
could be new products added to this sheet.
If I could have changes in say the 'product' and 'ID' columns in one sheet
and the changes in 'customer' column in another sheet it would solve another
issue although it's not very important.
I don't want to use Track changes since it gives the information in a more
random way when asked to produce a new sheet reporting changes.
Anyways, please help me if you can... desperately need this one

Thanks a lot in advance,

Epoch