Not sure who Brian actually is, but his post on OneNote PowerShell Provider is pretty cool. It documents another PowerShell Provider for One-Note. It allows you to see the contents of your OneNote Notebooks from PowerShell. Brian has created this cool provider which freely available under the Microsoft Community License.
The installation file is here: OneNotePowershell.msi, while the source files are here: OnPsProvider-1158.zip. When you install the provider,several sample scripts are also installed. And for the documentation that comes with the provider and the scripts, which comes in OneNote format, see here: OneNote PowerShell Documentation.
One small note - while the installation MSI installs this provider, you have to do some work in order to get it all installed into PowerShell. Read the documentation!