My good friend and co-presenter, the Dynamics GP Blogster himself, Mariano Gomez has managed to organise a fantastic series of posts about the architecture of Microsoft Dynamics GP
He is working with Tim Brookins (the father of Dexterity) to re-publish the architectural foundations white paper. He will also be getting some updates and comments from Tim to include with the series. Please make sure you have a read:
I have added the blog to the Microsoft Dynamics GP Blogs page and to the Blog Links on the left hand pane.