jquery live event for added dom elements

I want to add a class to any DOM element that is on the page now or in the future that has a specified class and meets some criteria

so for some pseudo code

$('.location').live('load',function(){
    if($(this).find('input:first').val().substr(0,1) == "!"){ $(this).addClass('hidden')}
});

of course this does nothing

EDIT NOTE

this does not work either

$('.location').live('load',function(){
    alert('adding location');
});