Quick start
Like someone said before, first read the stickies at the top of this forum.
Next, create a free Apple account and download and install the SDK on your Mac (not available for the PC).
Fire it up, download some of Apple's examples, and look around.
Buy some books and go through the tutorials (recommendations in the stickies).
Finally, after you learn how to write programs, and have something working that you think people would want,
then and only then give Apple your $99 for a paid Developer account (which lets you submit apps to the App store.