Anyone have any thoughts on how I go about this?

I need to build a recap workbook with data from several
other workbooks. The user would need to have a window to
choose the multiple workbooks from different directories
to recap (does excel have a file window other than
getopenfilename and saveasfilename?).

The workbooks would not have a constant number of rows.
In other words I would need to get the number of rows and
columns from each workbook prior to building the recap
workbook. Can I do this without opening each of the data
workbooks (each workbook is over 5 meg without data)?