If you insert a table it will always be on a new 'line'. If you want that table at the end of the cell whether or not it contains text:
Set a range to the cell
Omit the cell end character from the range.
Delete the last empty 'line'
Collapse the range
Insert the table e.g.
Code:
Dim oCell As Range
Set oCell = Selection.Cells(1).Range
oCell.End = oCell.End - 1
If oCell.Characters.Last = Chr(11) Or _
oCell.Characters.Last = Chr(13) Then
oCell.Characters.Last.Delete
End If
oCell.Collapse 0
oCell.Tables.Add oCell, 1, 1