Amazon Seller Inventory Lookup

What I need, really, is quite simple. I need a script developed, that will allow me to input the name of a seller, from any Amazon website (example, [login to view URL] or [login to view URL], etc), select the Amazon site I wish to search (again, for example, [login to view URL]) and... click "Submit" and your script, will return a list (csv, txt, .xls, file... any type you prefer) showing me all the items this seller presently has available for sale on that Amazon site. I will only need the basic information for each item (Product ID (also known as ASIN), product name/title, author, their price, and a few other basic details like this, which will be easy for you to obtain). I will be able to either either the seller name, as it appears on any Amazon product pages, or, their seller ID (a sample seller ID would be: A38KHSQZQX**** (the last four characters of this seller ID are hidden, because it belongs to a real seller, and I will only offer actual seller names/seller IDs to the selected bidder). Please note, that I will not have "Merchant IDs" available. This is why this script will be a little more advanced, and complex. All I have, will either be the seller name, or, seller ID (as shown above in the example). If you can build a clever script that can secure any given sellers list of items offered of any given Amazon site, with this information, the job is yours. Please note, some sellers, will have as many as 100,000 or more items listed, so this script will have to be solid, and able to run without crashing for extended periods of time. If it will time out, the script should have some kind of safety/backup feature, where data collected to that point will be written to the output file, and the script will again pick up and start running from the point where it stopped. Feel free to ask any questions, before submitting your bids. I have 3 sellers in mind that I am particularly interested in. They have inventory around 25,000 items and I want to replicate their inventory becuase I carry the same products.