Can I combine sheets from separate workbooks into one workbook?

I need to combine sheets from different Excel sources into a single workbook:  open a saved Excel workbook, grab a worksheet and put it into the spreadsheet control, do some manipulation.  Then open a different Excel workbook, grab another worksheet and add it as a new worksheet in the spreadsheet control's active workbook.  Then save the spreadsheet control's active workbook under a new name.  I can't seem to figure out if this is possible, or if so, how to do it.

I can add a new worksheet to the active workbook, but it's empty. I can't seem to set it to another worksheet loaded from a different Excel file.  I can copy values row by row and column by column, then then I lose all formatting, merges, etc.

Please let me know if I what I'm attempting is possible.