Something

function custom_init()
{
	custom.business = {'default' : {}};
	custom.business.add = function()
	{
		alert('added!');

		business_input = document.createElement("input");
		business_input.type = 'text';

		add_business = document.getElementById('add_business');
		add_business.insertBefore(business_input, add_business.parentNode);
	}
}
</script>