[maksqwerty]

function deleteRow(el)
{
    var del = el.parentNode.parentNode.rowIndex;
    table.deleteRow(del);
    while (table.rows[0]){
        updateRow(table.rows[del], del, false);
        del++;
    }

}

function insRow()
{
    var new_row = updateRow(clone.cloneNode(true), ++tbody.rows.length, true);
    tbody.appendChild(new_row);
}

 function updateRow(row, del)
 {
    row.cells[0].innerHTML = del;


    var inp1 = row.cells[1].getElementsByTagName('input')[0];
    inp1.id = 'inp1ut'+ del;
 

    var inp2 = row.cells[2].getElementsByTagName('input')[0];
    inp2.id = 'inp2ut'+ del;
  

   var sel1 = row.cells[3].getElementsByTagName('select')[0];
    sel1.id ='fertig'+ del;
 
    var sel2 =row.cells[4].getElementsByTagName('select')[0];
    sel2.id ='kost'+ del;

    var but1 = row.cells[5].getElementsByTagName('button')[0];
    but1.id = 'deletebutton'+del;

    return row;
}

Вот