gistfile1.js

  jQuery(document).ready(function() {
    var attributes = {}
    attributes["IT"] = 'data-amazon-it';
    attributes["GB"] = 'data-amazon-gb';

    var url = "http://freegeoip.net/json/";
    jQuery.getJSON(url, function(data) {
      var code = data.country_code;
      jQuery('[data-amazon]').each(function(index, link) {
        link = jQuery(link);
        link.attr('href', link.attr(attributes[code]));
      });
    });
  });