I hope I understand what you are asking. If this is a one-time event, then save the first file as an Excel workbook, not csv, that way you can have extra worksheets (csv files allow only one worksheet). As you open all the other csv files (you can do it at one time), right-click and choose "Move or Copy" and click the box below to "Create Copy" then select the original XL file (you saved above) as destination.