Protocols

Sizes of iPhone UI Elements
The Status Bar - hiding; setting the color
UIAlertView - pop-up alert messages
UINavigationController

Checklist for submitting an app to the app store
Build your app for distribution
What to do when your app gets approved

Setting up a web page for your app
Designing an iPhone-friendly Website
Promoting Your App

Apple's iPhone Dev Center is the place to go to become an iPhone developer.
Apple's iPhone Developer Forums are available to registered iPhone developers. These are a great place to find answers and get help.

iPhone Development Blog by Jeff LaMarche, author of the Beginning iPhone Development book.
Cocoa with Love - Matt Gallagher's Cocoa/iPhone programming blog, with example projects.
Theocacao - Scott Stevenson's Cocoa blog.
Mobile Orchard's iPhone App Developer's Blog - tips, news, interviews and tutorials for iPhone programmers.
iPhone Developer Tips - more useful code snippets.