Application that would searcch Amazon items by UPC and return ASIN and Sales Rank using API (No crawling))

I want to build an app that would use Amazon API to search products by UPC and return results with found multiple ASINs and Sales Rank. We would prepare File template with: 1. Item Number 2. Item Name 3. UPC 4. Item Cost Upload to application which would find matches to UPC (multiple matches) using Amazon API (no crawling!!) and return back ASINs of the item and Sales Ranks. I’m looking for a suggestion on what is better to use as a platform (web based cloud app or standalone win32) – since it will take a lot of time to process the file I’m thinking Web based is the way to go. Plus I would want an email notification to a user once file is processed and ready to be downloaded. Meaning we would have to register users with his username, password and email address to receive this notification. If you up for a challenge let me know and we will work out details on how app should look. The templates attached