I couldn't find the Relative/Absolute icon anywhere in any of the
'customize' dialogue box tabs. (xl2003)
You could try resetting the toolbar:
Tools>Customize>Toolbars. Scroll down and find the Stop Recording
Toolbar.Click on it and "Reset".
Otherwise this single line in a macro might do it:

Application.CommandBars("Stop Recording").Controls.Add Type:= _
msoControlButton, ID:=896

(you could just execute this line once in the Immediate window of the
Visual Basic Editor instead (Ctrl+G to get the Immediate Window
visible in the VBE)).