We have just released support for NewEgg Marketplace.
Teapplix fetch orders from NewEgg via ftp and confirms orders as shipped automatically. To setup NewEgg integration, go to Setup => Others => Shipping Carts, and select "newegg" as your source and fill in your ftp details.
You need to ask NewEgg for ftp access. Also, you need to setup your NewEgg account to generate order reports in CSV format.