If you are playing with the Windows 8 developer preview as I have been since the Build conference, you may have noticed a lack of documentation causing you to hunt and peck through the Object Browser to try to find methods to accomplish tasks that you used to do. To make things easier, Microsoft has released a number of Metro style application samples that you can download individually, or all of them together in the bulk sample pack. At this point, they are the best way to learn the ways that the WinRT libraries were intended to be used. They are reasonably well documented. In addition, expect for the number of samples to continue to grow. I know that the teams added 23 VB samples alone in the last 2 weeks.
If you have further questions about Windows 8, your best bet is to head over to the Windows 8 Forums and join in on the conversation. If you still need to download the bits, grab them from the Windows dev center.