Dialog Box with drop-down lists for ordering items on website.

I have an online store that I am building from a template. I need to add a very detailed dialog box with multiple drop down lists that reflect the specific items for sale. These lists will allow the customer to select specific item details and, as a result, the total amount due will then be reflected. Please go to this website and look at the order form for exactly what I am looking for: [login to view URL]