QTP's design lends well to stackable parameterization... For example here, you can use parameterization to control your parameterization ;)
'where Config.xls is an excel file with a tab/sheet called "Config" and a column called "Filename" that contains the filenames of the workbooks containing the data.
DataTable.AddSheet "Config"
DataTable.ImportSheet ("Config", "c:\Automation\Config.xls")
DataTable.AddSheet "Data"
DataTable.ImportSheet (DataTable("Filename","Config"), "Data", "Data") 'this assumes the data is on a sheet called "Data" in the excel file, and it ends up in the datatable as a sheet called "Data"
Or, you could even put all the data in one workbook on different sheets and include a column that names the data sheets...
DataTable.AddSheet "Config"
DataTable.ImportSheet ("Config", "c:\Automation\Config.xls")
DataTable.AddSheet "Data"
DataTable.ImportSheet (DataTable("Filename","Config"), DataTable("Sheetname","Config"), "Data")
So, you setup your test by editing Config.xls to control which datasheet ends up in the "Data" sheet in the QTP datatable :)