I had posted about the same issue with extra information, but it was deleted. However, I found a solution so you can get the layout folder populated with the blank activity.
Instead of using the ADT package, download Eclipse and the SDK separately. Follow the details here, but download and unpack the SDK first. Click the DOWNLOAD FOR OTHER PLATFORMS link.
You will also need the location of your java JRE bin folder.
I hope that helps,
Lee.