do you have a canon digi cam ?? (or know someone who has a canon digi cam ??)
if so, they have a "stitch mode" which you can take multi pics, and there's a pgrm to stitch them together to become one...
(not perfect, but good enough...)
as for avoiding different angles and stuffs, I think if you measure your distance, and use the same zoom, same lighting, same everything when taking the pics, just move the digi cam across, you should get pics that are workable in photoshop.
I don't know, but from your pic, seems like a normal scanner will not work... how about a handheld scanner ?? (know anyone has one of those ??) those might work...