Online ordering custom forms

Hello developers, I am in need of a solution for my business. I currently have a website which needs to be enhanced. I would like my clients to login and see their most commonly ordered items. They should be able to simply enter the quantity required. There should be room for them to enter any additional items required that are not on the list. Once they submit the order - there should be 2 emails produced. 1 confirming their order, 1 sent to me showing a pending order. I would also like a purchase order created within Quickbooks. Quickbooks has a free application that allows development and communication with the software. Please look into it. I do have a database of over 40,000 items. My clients usually only use about max 100 items - they vary from customer to customer. I have the Economy hosting plan with Godaddy. It should support multiple platforms. Please see the link <[login to view URL]>