PerfectSolution

New official plugin for Quickpay v10+ 
With WP eCommerce Quickpay, you are able to integrate your Quickpay gateway with your WP eCommerce webshop. With a wide list of API features including secure capturing, refunding and cancelling payments directly from your WP eCommerce order overview.

WP eCommerce Quickpay

Integrates your Quickpay payment gateway into your WP eCommerce webshop.

analogrithems

This is a plugin for WordPress e-Commerce <a href="http://getshopped.org/" rel="nofollow ugc">http://getshopped.org/</a>
It provides some advanced functionality to really help people get up and going quickly with WordPress eCommerce. It allows you to do mass imports of products, users and orders. Or perhaps you want to pull the data back out. Well the export can do that for you. You have the choice of working with any of the following formats 
 * CSV 
 * XML 
 * SQL
This plugin has many uses such as migrating from an old outdated ecommerce cart like oscommerce or zencart over to WordPress ecommerce. 
This plugin even implements RPC XML so you can access your orders, products and user information via a nice easy to use XML api. 
New API’s are being added to support common Order Management Solutions. If you have an order management system you would like integrated with WordPress ecommerce be sure to contact be at the site below. 
See the full documentation at http://www.analogrithems.com/rant/portfolio/wordpress-ecommerce-data-feeder/

eCommerce Feeder

WP eCommerce Feeder plugin used to import and export data for products, customers and order history.

WP eCommerce Quickpay vs eCommerce Feeder