I have been struggling during the last weeks to get 32×32 icons from Office 2007 and yesterday I found the 2007 Office System Add-In: Icons Gallery. Also, a question that appears from time to time in the forums is how to get the numerical indexes of the Office bitmaps to use when calling the AddNamedCommand method, and incredible as it is, I think that Microsoft never documented this for that method in MSDN, and there used to be years ago an Excel spreadsheet (quite difficult to find then, and impossible nowadays, likely removed from MSDN) to help in the task with VB5/VB6/Office add-ins. Fortunately I put a copy in the Files section of the Yahoo forum for VS.NET add-ins that I used to visit until a couple of years ago before moving to the MSDN forum, and I had a copy of the Excel file in my own hard disk. I have documented all this in my latest article:

HOWTO: Get Microsoft Office bitmaps for Visual Studio add-ins
http://www.mztools.com/articles/2008/MZ2008020.aspx