Custom Ribbon Add-in

Using Excel 2007, I have a .xlam add-in that displays a new ribbon with some custom functions. I'd like to add a few of the standard Excel buttons onto this ribbon as well, so that when a user loads the add-in, they see my custom functions and the frequently used standard commands all on one ribbon.

You add them much the same way you added your own buttons - see Ron's site here for examples.