To get the spec of what you want then either code it up, search for a solution or put out a RFQ.
Can any suggest me an automated/real-time approach that can help me manage the inventory of Magento-based eCommerce store on Etsy marketplace? Is there any means by which I can manage the order from a single interface.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic