PDFJoiner
http://qetipadgu.org/software/
joinPDF
http://www.mac4ever.de/software/
Create, a cool OSX app that actually is older than OSX.
It was first written for the Next.
http://www.stone.com/
Combine PDFs freeware
http://www.monkeybreadsoftware.de/Freeware/CombinePDFs.shtml
