Create Visio Drawings based on images

Need to re-create a number of application drawings. I only have the images and need them to be duplicated in Visio 2002/2003 (preferrably 2003). I have uploaded one of the most complicated and one of the simplest diagrams for your reference. 71 drawings total. All the drawings need to be redone with a consistent colour scheme, font, and font size. When a single drawing is printed, the drawing should fit on a single A4 page.