Basic Inventory Management (Amazon SC)

Looking to build a basic inventory management system for our ecommerce backend. Must have experience with Amazon Seller Central. Project should preferably be built on Google's Apps Engine. Otherwise, a popular open source language combination. (eg. PHP/MySql) What is needed is a basic database which will pull my inventory information from Amazon Seller Central on a daily (or hourly) basis. The above Amazon file only contains the ASIN, SKU, price and condition of each SKU/product. This database will then have to populate all other fields needed to for a retail ecommerce catalog. Using the above file, you will know which products we need the information for. You will take every ASIN from the above file and then call Amazon's web service API to gather the rest of the information; such as product descriptions, images and so on. This information only needs to be pulled once for each product. The application will pull the above file again from Amazon daily in order to see if there are new ASIN's in the file in order to gather new information for this product to be added to the above database. ASIN's that have been removed will also be removed from the database. Another reason for pulling this file daily (or hourly) will be in order to update the current pricing information. The application will then generate daily (or hourly) a csv (or tab-delimited) file from the database which will automatically be exported onto a remote server to be used for the ecommerce catalog. This file will include all inventory, pricing and description information in the database. This file is actually going to a Magento website, so if you have better way to connect (eg. through the Magento API, it would be even better.) You must build the entire project with an easy to use front-end to manage these tasks. If the project is done well, we will expand on in to include functions.