Custom Contact Form With File Upload

What I'm looking for is when a customer buys one of my products after they purchase I have it set so after the go to paypal it takes them back to the main site, I would like to set it so when the purchase the page it brings them to is a form where they can input there info and select a file to be upload

The site is a printing site where they can order business cards and other items, if they don't need me to design it and they have there file I would like for them to upload a file after they pay.

the is is http://www.digitaldigg.com/shop

If you need we can go over all this by Phone or Skype.

skype is digital.digg

Instead of doing this after payment, you could do it before payment using readyman's Global Mega Options.