You'll need to make a reference (menu option 'Project\References') to Microsoft 9.0 Excel Object Library, and then use code along the lines of..
Code:
Dim ExApp As Excel.Application
Set ExApp = New Excel.Application
' make Excel visible
ExApp.Visible = True
' open the specified worksheet
ExApp.Workbooks.Open "c:\my documents\whatever.xls"
' select Sheet 1
ExApp.Sheets("Sheet 1").Select
' get the text from different cells
MsgBox "Text in cell A1 is "+Range("A1").text
MsgBox "Text in cell B2 is "+Range("B2").text
MsgBox "Text in cell C5 is "+Range("C5").text
' close the workbook
ExApp.Workbooks.Close
' close Excel
ExApp.Quit
Try recording some macros in Excel, that'll help you generate some more code.