You can use the Excel Object Model to automate Excel from VB 6.
VB Code:
  1. Option Explicit
  2. 'Add a reference to MS Excel xx.0 Object Library
  3. Private Sub Command1_Click()
  4.     Dim oApp As Excel.Application
  5.     Dim oWB As Excel.Workbook
  6.     Set oApp = New Excel.Application
  7.     Set oWB = oApp.Workbooks.Open("C:\Book1.xls")
  8.     oWB.Sheets("Sheet1").Cells(1, 1) = "My Name"
  9.     oWB.Save
  10.     oWB.Sheets("Sheet1").PrintOut [From], [To], [Copies], [Preview], [ActivePrinter], [PrintToFile], [Collate], [PrToFileName]
  11.     oWB.Close
  12.     Set oWB = Nothing
  13.     oApp.Quit
  14.     Set oApp = Nothing
  15. End Sub