Adding your items to Google Base can be confusing. You don't have to understand how it works, or how the RSS feed works to do this. Here are some links to tutorials and information to help you figure out how to set it up. Once it is set up, you don't have to do it again. You can set it to automatically update on its own.
If you have any trouble getting it to work, you are welcome to contact me, LazyTcrochet, or contact support@Etsy.com. They were very helpful when I had issues with it.
The best online tutorial for this is on GoTo's blog: http://www.gotogreatpanes.com/blog/2009/01/31/etsy-rss-and-google-base/
Be sure to read the comments under the post as well. Now that Etsy's RSS feed works with Google Base, it's much easier to schedule the data feed to update automatically. I have mine set to update once a week. If you are loading many new items every day, you may want to set yours to update every day. If your items aren't changing that much throughout the week, then once a week should be fine. I think Google may have an issue about updating your feed too often if it's not necessary.
Don't be intimidated by all this. Sign up for a Google account, if you haven't already, and go to Google Base. Open a new tab or page to have access to your shop's main page. And open another tab or page with the tutorial instructions. Then you can go back and forth while you are working on it.
There is more information in the "Storque" article here... http://www.etsy.com/storque/etsy-news/tech-updates-feed-enhancements-google-base-and-more-3173/
Etsy posted instructions there, as well as in the selling FAQ's here... http://www.etsy.com/faq_selling.php#feed_base
Once you have it set up, it may take Google awhile to process the information. You can check back and make sure that it says that it was successful and that your items are "published and searchable." There may be certain keywords in your listings that they may find objectionable and a scheduled upload may "fail" even though it has gone through successfully many times before. Just check in once in awhile to make sure that all is well.