I have this excel worksheet
A B c
foo1 joo1 loo1
foo1 joo2 loo2
foo2 joo3 loo3
foo2 joo4
If you are willing to write a macro...
Click the first "foo1" cell and run this. It will join the foo1's then the foo2's until it hits a blank cell. If you've never written a macro before perhaps we can walk you thru it.
Sub JoinThem()
' Go until blank cell (first click at upper left of range)
Do While ActiveCell.Value <> ""
' If this row macthes the next row
If ActiveCell.Value = ActiveCell.Offset(1, 0).Value Then
' Join first column overwriting the values
ActiveCell.Offset(0, 1) = ActiveCell.Offset(0, 1).Value & ", " & ActiveCell.Offset(1, 1).Value
' and Join the second column too
ActiveCell.Offset(0, 2) = ActiveCell.Offset(0, 2).Value & ", " & ActiveCell.Offset(1, 2).Value
' Since we placed the data into one row get rid of the row
ActiveCell.Offset(1, 0).EntireRow.Delete
Else
' Next row does not match, move down one
ActiveCell.Offset(1, 0).Select
End If
Loop
End Sub