Vault tool windows are available in Visual Studio under the View menu. The primary tool window that you will need to interact with the Enhanced Client is Pending Changes.  This tool window will allow you to see at a glance all of the changes that you have yet to commit to the repository.  If this view is accidentally closed, you can open it again using the View->Vault Professional Pending Changes menu item.

The Notifications window provides real-time notifications of updates to your source control repository and work item projects.

To open the Notifications window in Visual Studio, select View >Vault Professional Notifications.

The Work Item Tracking window allows you to view, add, modify, and query work items within the Visual Studio development environment. To open the Work Items window in Visual Studio, select View->Vault Professional->Work Item Tracking.