lookup problem

Hi I would like to create formulae to automatically update data between worksheets and also between work books. I have attached a copy of the workbook.
I would like to update the prices in service kit contents column H via the part number in column B.
To the part number in numerical column A from the price in column I.
Also is possible to hide columns D to H so they cannot be unhidden when passing the workbook on electronically.
The workbook is 900 rows long.

Thanks in advance

Andy