This will require code, I believe. I recorded this:
Sub Macro1()
Columns("A:C"

.Select
Selection.SpecialCells(xlCellTypeConstants, 23).Select
With Selection.Interior
.ColorIndex = 6
.Pattern = xlSolid
End With
Range("A1"

.Select
End Sub
It selects Columns A, B, and C and finds the cells that contains values, not formulas, and makes them yellow.
You find the constants by hitting Edit-Goto, hit the Special button and then hit the Constants button (note the other choices under there also).
So if you can figure out how to find your constants, and you can figure out how to record a macro and put a button for it on the toolbar, you should be able to do this.
Perhaps you want it to be dynamic? This will require a Worksheet change event macro. In other words, someone who can write code (not just record it).
Let us know.
techsupportgirl@home.com
Brainbench MVP for Microsoft Word at