That last post on loading multiple Excel files is probably going to be less useful if you have files in the new Excel 2007 XSLX file format. The built-in Excel source component in SSIS only works with the "classic" XLS file format. Fortunately, Microsoft has made available for download a set of 2007 Office System Driver: Data Connectivity Components that allow you to connect to XSLX files via OLE DB or ODBC.
There's also a good article on this on the ssis.wik.is web site, with a few more details than you'll find on the download page.
 I think that "classic" has a much nicer ring to it than "legacy"
 Which was, of course, the new "old"
 Which was, of course, the old "old"