How to sum across excel worksheets in the same book for a specific value?

Question by dewz: How to sum across excel worksheets in the same book for a specific value?
I have an excel workbook that I use for a catalog. The first tab is a summary tab of the product # and price. Every other tab in the workbook is a product tab (sheet 2 = PRD 2, etc). The product tabs contains the product details, etc. The last tab is called end.
I update my product prices on their specific tabs, NOT on the first summary tab.

MY question: I would like to use a formula on the summary

Read more tab book...