I just save the previus week total (that reason I put LT numbers on the table now) then make a simple math THIS WEEK TOTAL - PREVIOUS WEEK TOTAL.
Of course if there are any adjustment in previous weeks I can't say when or how much.
About the others games... some VGC Pro users has access to TOP200.
Just keep a close watch on GT5. I've never really been so into a single title's sales before, but when something as monstrous as GT5 comes along, it's nice to see how it stacks up in such a strong franchise.