Besides the official documentation and the Quickstart, there are many useful resources for Zend Framework, like blogs and Twitter. I did my best to collect them. If you know something that's not listed here, but should be, please leave a comment and I'll update the post :)
Update #1 (seconds after publishing): Gotta love Twitter. Already got a message that I missed a blog. List is updated.
Update #2: Added more blogs to the list, thanks Jani for the recommendations!
Update #3: Thanks to Federico and Pablo, even more stuff to add :)
Update #4: Thank you Jon and Cal :)
Update #5: This is growing up into a pretty big list :) new stuff added!
Update #6: Should I keep adding these Update #x lines? :)
Update #7: A bunch of new stuff!
Update #8: A new ZF application via Federico's blog!
Blogs are probably the most important resources out there. Besides the posts, comments can add a great value to the topic, so be sure to read them too. Here are the blogs that have posts on ZF and were updated recently (in the past month or two):
Also, I recommend subscribing to PHPDeveloper's and Zend Developer Zone's feeds, just in case I missed some good blogs ;)
On Twitter there are many friendly developers willing to help out with any problems related to Zend Framework just write your question with a ZF hashtag and someone will most likely show up with the answer :)
two books are a must read. That is all :)
Surviving The Deep End a free online book that is written chapter by chapter. Author is Pádraic Brady:
The book was written to guide readers through the metaphorical "Deep End". It's the place you find yourself in when you complete a few tutorials and scan through the Reference Guide, where you are buried in knowledge up to your neck but without a clue about how to bind it all together effectively into an application. This take on the Zend Framework offers a survival guide, boosting your understanding of the framework and how it all fits together by following the development of a single application from start to finish. I'll even throw in a few bad jokes for free.
Zend Framework in Action OK, this book is not an online resource, but it is great and surely must be mentioned :) Authors are Rob Allen, Nick Lo and Steven Brown:
Zend Framework in Action is a book that covers all you need to know to get started with the Zend Framework.
The first part of the book works through the creation of web site using the MVC components (Zend_Controller, Zend_View and Zend_Db). The book then follows on by looking at user authentication and access control, forms, searching and email to round out the application. After considering deployment issues, we then look at other components that add value to a web site; including web services, PDF creation, internationalisation and caching.
Guide to Programming with Zend Framework another great book, a must have. Written by Cal Evans.
This book covers much of the primary functionality offered by the Zend Framework, and works well both as a thorough introduction to its use and as a reference for higher-level tasks
Beginning Zend Framework written by Armando Padilla
Beginning Zend Framework is a beginner’s guide to learning and using the Zend Framework. It covers everything from the installation to the various features of the framework to get the reader up and running quickly.
Easy PHP Websites with Zend Framework by Jason Gilmore
Easy PHP Websites with the Zend Framework is the ultimate guide to building powerful PHP websites. Combining over 330 pages of instruction with almost 5 hours of online video and all of the example code, you'll have everything you need to learn PHP faster and more effectively than you ever imagined.
Applications powered by ZF
Wanna see what's ZF capable of?
Of course, there's the good ol' IRC, channels are #zftalk and #zftalk.dev. For more information, visit ZFTalk.
Jani Hartikainen's Packageizer is a great tool to get only those ZF components you need.
Scienta ZF Debug Bar an awesome plugin for Zend Framework which injects into every request a snippet of HTML with commonly used debug information.
There's also the Zend Framework Forum. For those of you who understand it, here's a German forum www.zfforum.de.
The Zend Framework Wiki and the Zend Framework Issue Tracker are also very helpful, so, be sure to check them out.
The unofficial PEAR channel for the Zend Framework can be found at http://zend.googlecode.com/.
That's all from me. This are the resources I found useful and hopefully are and will be useful for you too :)
Do you know anything I missed? If so, please, leave a comment and I'll update the post :)