Cobol and RPG. OK, you're older than most. Yea, so am I.

Given that you are an experienced coder, I think a good first start maybe the Stanford iPad and iPhone App Development course on iTunes. I clicked on 'Name' to sort the classes properly. The first one is the most important. Try to 'get' the MVC (Model View Controller) concept.

The good thing about the latest version of the above course as I understand it is that it uses XCode 4 of iOS 5. That makes it very current. Some of the books you have may use the older Xcode 3 and not mention newer capabilities of iOS 5.

Apple has many free samples. They tend to be mentioned via there web site when you look up things such as location services. Type those two words into the search box of iOS Developer Library at the top right.

The books will probably be better to start with than most tutorials or samples. Rather than over saturate your learning, I think concentrating on what you have makes more sense.

StackOverflow.com can be a good place to learn things. Many common questions have been asked and answered there along with more subtle ones.

You didn't mention what books you have. Others may have some opinion on them and where to start first. For instance if you have a straight Objective-C book, you should likely go through that first.

Good luck on the adventure.