Also, storyboards are really powerful and can save you a lot of time once you learn them.
I'm mostly a Rails/Ruby dev as well but am doing more iOS. My recommended resources are:
1. BIG Nerd Ranch book (best book IMO) http://www.amazon.com/iOS-Programming-Ranch-Guide-Guides/dp/...
2. Programming iOS (5|6) by Neuburg (either version is fine) http://www.amazon.com/Programming-iOS-6-Matt-Neuburg/dp/1449...
3. Ray Wenderlich blog and tutorials bundle (worth the money) http://www.raywenderlich.com/store/ios-5-and-ios-6-by-tutori... His storyboard tutorials are great
4. NSScreencast (think RailsCasts for iOS. Not as thorough yet, but worth the money) http://nsscreencast.com/
5. Do a week-long, in person class such as http://pragmaticstudio.com/ios if you can afford it
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Other than that, I really haven't run into issues I couldn't figure out via Stackoverflow or Apple's docs/samples.
The real issue for me was wrapping my head around the frameworks and understanding how it differs from Rails/web world. You might find it helpful to just take a week off and bury yourself in it. Try and pick a very simple (but useful/functional) app you can build and ship in a couple weeks. Give yourself a deadline and do it.
By the second chapter I felt confident enough to start trying things out on my own and tutorials made a lot more sense.
In relation to the criteria you raised the book is a good fit.
- I understand most of the basic concepts, but cannot implement them via code
I think this is particularly true with iOS programming. The book is more written in a tutorial / HowTo style (i.e. the book gives a step by step walkthrough to create an example program). Most importantly it specifies how to use the IDE to do GUI building.
- I am a person that does really well when I have a set path
Me too. Each chapter is an exercise designed to teach you some part of the iOS library. There about 30 chapters in the book and each chapter can be completed in about 2 hours.
If you want an intensive study of Objective C itself, look at the Kochan book. It's the bible.
http://www.stanford.edu/class/cs193p/cgi-bin/drupal/
http://www.amazon.com/Programming-Objective-C-Edition-Develo...
http://www.amazon.com/iOS-Programming-Ranch-Guide-Guides/dp/...
Books
http://www.amazon.com/Objective-C-Programming-Ranch-Guide-Gu...
http://www.amazon.com/iOS-Programming-Ranch-Edition-Guides/d...
Videos
http://www.codeschool.com/paths/ios
http://teamtreehouse.com/library/ios-development