Along with a developer account, http://developer.Force.com provides additional resources for developers.
It provides:
Additional documentation
Online forums
Code share
All these resources can be accessed free with a single developer account. Additional community blogs and resources are available in the final chapter of the book.
Note
If you are on Twitter, additional help can be found using hash-tag #AskForce and #AskSalesforce with the Salesforce Community. You may also address the Tweet to @_siddhesh.