How to Override/Rewrite Magento core blocks and controllers?
http://tutorialmagento.com/how-to-override-rewrite-magento-core-blocks-and-controllers
http://excellencemagentoblog.com/magento-part10-series-overriding
http://blog.chapagain.com.np/magento-block-controller-model-helper-override/
Magento video tutorial
http://leveluptuts.com/tutorials/magento-community-tutorials
http://tutorialmagento.com/how-to-override-rewrite-magento-core-blocks-and-controllers
http://excellencemagentoblog.com/magento-part10-series-overriding
http://blog.chapagain.com.np/magento-block-controller-model-helper-override/
Magento video tutorial
http://leveluptuts.com/tutorials/magento-community-tutorials
