First off, check to see if your shop has a syndication feed or not here:
It'll either say "active" or "pending."
If you're active, it'll look like this:
If you're pending, it'll look like this:
Keep checking back till you're in active status. I can't tell you when that will be, but if you check into this thread here on Etsy, they're answering questions.
Next, go to "Your Etsy":
Then, if you're active, in "your etsy", use the "select all" and "deactivate" buttons at the bottom of each page of your shop
Once you've done this, then go to the inactive items tab:
"Select all" again and "activate".
And all your items are magically inserted. Just takes once - you don't have to do this for renews or new listings, as that's automatic, but your older listings aren't there yet. If you've got a custom arrangement in your shop, you'll lose it using this method, though - just a warning.