Question says it all...
You can get this functionality in Netbeans as described in this article from the bakery.
http://bakery.cakephp.org/articles/view/model-based-code-insight-and-completion-in-netbeans
You can also do the same thing in Eclipse PDT or Aptana.
http://mark-story.com/posts/view/code-completion-for-cakephp-in-eclipse
All of these IDEs are free. Although they are both
Now netbeans has a plugin for CakePHP.