In this line (connect.vb, after creating an add-in through the built in
VS.Net Add-in template),
Look at the '59' :

toolsMenuName = "Tools"
CommandObj = _applicationObject.Commands.AddNamedCommand(objAddin,
"My_Add-In", "My_Add-In", "Executes my stuff", True, 59, Nothing, 1 + 2)
CommandObj.AddControl(toolsMenuName)

That number adds the 'smiley face' icon for the Add-in entry in the Tools
menu, when the Add-in is used. If you change that, to another number,
another icon will appear.

Where can I find a list of the different icons that can be used here (what
numbers use what icon image)?