How to create a pdf? Examples.

Albe

I highly recommend you get a copy of Aaron Hillgrass' book "Cocoa Programming for Mac OS X".  He deals with this (and many other matters).  Cocoa is wonderful technology - however there's quite a steep learning curve for the beginner.  There are three hurdles:
1) The Obj/C Obj/C++ language.  This C with additional stuff.  However the object model is rather different from C++2) The Cocoa Frameworks.  Apple provide vast libraries of classes include PDF support3) X-Code and InterfaceBuilder.  The tools for creating apps with Cocoa.Each of these matters have to be learned and without a good guide, you are unlikely to succeed.  Apple do provide a lot of documentation and a few tutorials.  However everybody appears to agree that the road to understanding is Aaron's book.  http://www.amazon.com/Cocoa-Programming-Mac-OS-3rd/dp/0321503619/ref=dp_ob_title_bk/185-1719504-9244727