Microsoft 2007

I think you mean you want to view two worksheets from the same workbook at the same time

To do this ensure the workbook in question is open and that it is the only workbook open then and go to the view ribbon. From the Window group select New Window.

Excel will open a virtual copy of the workbook. You will know this because the name of the workbook in the title bar will have a :2 at the end indicating you have a virtual window open of the workbook

For all intents and purposes it is the same workbook typing in one will place the data into another.

To arrange them side by side select the view tab again and click arrange all ensure you check the box which states Windows of active workbook then select Vertical. You will have the same workbook displayed then you can view another sheet of it while looking at sheet 1.

I hope that helps.