Here is the article which gives an idea how to override the custom homepage of Cake PHP and get a new/your own homepage.
http://pinoytech.org/blog/post/How-to-Setup-the-Home-Page-on-your-CakePHP-Application
Basically, you have to modify the Routes.php in app/config directory.
Here is piece of code, which will make your life easier.
Router::connect('/', array('controller' => 'blog', 'action' => 'index';
