I just started VBA today, but from what I know so far, I would guess
you could write it similar to this:
'The Selection has already been made by the user when the macro is run, so:
I haven't tried it, it's just a quick shot to give an idea.
Dim i as Long, j as Long
For i=1 to Selection.rows.count Step 1
For j=1 to Selection.columns.count Step 1
'DoStuff like msgbox Selection.Cells(i,j).Value
"My brain is just no good at being a relational Database - my relations suck real bad!"