Auto Number Forms Prepared In Excel

I have created several forms using Excel (2000/2003), i.e., purchase orders, for my company.

We need the forms to auto number in increments of 1 (001, 002, 003) and only increment when the document is saved.

We also need to be able to track who requested the purchase order form/number. But if I could just get it to auto number to start with that would be great. There will be multiple users needing purchase order numbers.

Can anyone help (I’m an above average Excel user, but not really a whiz when it comes to programming codes).

Thanks.