Fileplanet announced a sneak peek of Age of Conan's first expansion for their subscribers. If you're among that number, you have access to a key via their promotion page. If you're not, Fileplanet will of course be very happy to let you subscribe via the same page. While the expansion itself won't be available until tomorrow, the download is available now to allow subscribers to install ahead of time and jump right in once the sneak peek begins.
This is the full expansion rather than a limited version, but it's important to note that the page specifies North American subscribers as well as a limited number of keys, so grab one quickly if you're interested!