If the url is determined by a controller and an action you can use this:
{{store url="module/controller/action"}}
If the url is to a cms page you this:
{{store _direct="url-key-here"}}
if you want some query params also like /some-ulr?a=2&b=5
use one of the methods above and add a _query
parameter.
{{store url="module/controller/action" _query="a=2&b=5"}}
{{store _direct="url-key-here" _query="a=2&b=5"}}
[EDIT]
You can get the same urls in a template file like this:
$this->getUrl('module/controller/action'); //for controller pages
$this->getUrl('', array('_direct'=>'some-url-key')); //for cms pages
$this->getUrl('module/controller/action', array('_query'=>'a=2&b=5')); //for query params
$this->getUrl('', array('_direct'=>'some-url-key', '_query'=>'a=2&b=5')); //for query params