For everybody else: within the full version of acrobat you can choose "document" and then "insert pages". From there you can choose all sorts of document types (pdf, tiff, jpeg, etc.) and it will add them as pages into your pdf.
Alternatively you could bring them all into a page layout program like Quark Xpress or Macromedia Freehand and print it as a PDF using Acrobat Distiller or the "print to PDF" plugin.
simon