I am running Outlook 2003 and setup the Inspectors collection in VS2005 and I cannot get the new Inspector routine to fire I used the While You were Out sample. Any Suggestions Here is the code I used. BTW, the items add, change and remove work in the WYWO sample. And intellisense works with the _Inspectors object.
Imports Office = Microsoft.Office.Core
Imports System.Runtime.InteropServices
Imports Microsoft.Win32
Imports Microsoft.Office.Interop.Outlook
Imports Microsoft.VisualStudio.Tools.Applications.Runtime
Imports System
Friend Class WywoAddIn
Implements IDisposable
Private WithEvents _Inspectors As Outlook.Inspectors
Private Sub _Inspectors_NewInspector(ByVal Inspector As Microsoft.Office.Interop.Outlook.Inspector) Handles _Inspectors.NewInspector
MsgBox("New inspector")
End Sub

Outlook 2003 New inspector does not fire with VS2005
Darren Kennedy
' Add an event handler to to be invoked every time a new
' inspector is created. Inspectors are handles to
' individual Outlook windows.
' This event handler will be invoked every time a new window is
' created.
AddHandler Me.ActiveExplorer().Application.Inspectors.NewInspector, AddressOf Inspectors_NewInspector
Also take a look at search out on http://www.outlookcode.com for more detailed examples.
Roosevelt [MSFT]