BO provides a CmdBars class for this purpose. You can create a new toolbar or add buttons to existing toolbars with this.
There is an example here where the add-in adds a pop-up menu to the main toolbar. You can use a similar method to create new toolbars and add faces to them. Distributing this as an add-in is usually the most efficient way for ppl to use the functionality.
Check out the other post, it might give you some ideas on this.
avaksi 
(BOB member since 2002-08-22)