Easy Populate:

Easy Populate makes it simple to populate your OSC store with products without using the web interface at all.

Easy Populate lets you download all your products into a csv file, edit them in the spreadsheet of your choice, and the reupload them to update your products, changing prices, categories, quantities, etc.

If new manufacturers, categories, or subcategories are found in the data, they are created for you on the fly.

This is based on the Excel Upload 1.51 from dynamok.