Setting And Getting Cookies To set cookies:

Here is the way to go…….

Mage::getModel('core/cookie')->set('cookie_name', 'cookie_value', 0); # session cookie

Mage::getModel('core/cookie')->set('cookie_name', 'cookie_value', 60); #lasts 60 seconds

// To Get Cookies:

Mage::getModel('core/cookie')->get('made_productalerts_stock');

 

reference: http://jaseir.com/magento/setting-and-getting-cookies-to-set-cookies/