Como Unir Pdf En Uno Solo

For fun, I'm trying to use an Apple PowerBook 5300c (Mac OS 7.5.2) to do some programming. I've found the software I want to use (thanks to some answers on SO) but I'm unfamiliar with these formats (I've always been a PC guy). I've searched for things like "Windows Mac write floppy", but I only really see pages about reading Mac format on PC (not exactly what I need).