I spent a few more hours trying to figure this out. I now think that is impossible to figure out without more of the "guts" of the game. This Addon seems to look in the warlock spell book and identifies textures rather than the names of the spells. As the button textures are recycled what they represent is context dependent.
Does anyone know of a list where the texture is shown along with its root location/name?
to wit
Demonomicon.SummonTab = [[Interface\Icons\Spell_Shadow_Metamorphosis]]
this does not mean the warlock spell metamorphosis, it must mean the icon, which is used on the warlocks "demon" tab.
rhamses