you might try to use Worksheet_Change event (go to sheet tab, right-
click on it, click Show code, instead of "(General)" select
"Worksheet" and then "Change" in the rightmost window)

Private Sub Worksheet_Change(ByVal Target As Range)
Cells(Selection.Row - 1, 1) = Time
End Sub

provided entering data moves you 1 row down
however this will cause time to be entered to cells in 1st column also
on editing any cell

HIH