Code:
Private Sub DoSomethingInExcel() 
Dim xlapp As Object 'Excel.Application 
Dim xlbook As Object 'Excel.Workbook 
  ' Start Excel 
  Set xlapp = CreateObject("Excel.Application") 
  ' Add new workbook 
  Set xlbook = xlapp.Workbooks.Add

  ' Do something...

  ' Release modules & clean up 
  xlbook.Saved = true  ' or false 
  xlapp.Quit 
  Set xlbook = Nothing: Set xlapp = Nothing 
End Sub