X-Cart module, which would help you export easy your products into Google Base engine.
Main features of this X Cart Mod:
easy to use and configure
multilanguage support
multicurrency support
ability to set you location
ability to set you payments you accept
ability to export only selected categories
ability to include/exclude products marked "our of stock"
ability to include/exclude with zero quantity
ability to limit number of products exported
ability to set currency that is used during export
ability to customize name of the export file
inline text recommendations for fast initial configuration.