From Ted Buckenham:
The Windows 8 shutdown process is obviously different than in previous versions. I found lots of workarounds to this but nothing was simple. I combined some VB code and Java script to make this app that does not require any other software (other than what is installed on most computers) to function.
When you click the tile, the 'classic' Windows Shutdown Box appears giving you the option to shutdown, restart, etc.
If you can setup an e-mail account, you can probably install this app.
Here are the steps:
1) Download and unzip the files into a folder. (anywhere on your computer)
2) Right-Click the 'Power' app that is created in the folder, select 'Pin to Start'
3) Move the tile to where you want it on the screen (optional)
4) Enjoy a simple way to shutdown, restart, hibernate, etc. your computer.