getParam http://jsbin.com/EkEbUki/1/edit

getParam.js

var getParam = function( name ) {
	var result = '';
	var thisUrl = unescape(location.href);
	var params = thisUrl.substring(thisUrl.indexOf('?')+1).split('&');
	for(var i = 0 ; i < params.length ; i++){
		var keyValue = params[i].split('=');
		if(keyValue[0].toUpperCase() == name.toUpperCase()){
			result = keyValue[1];
			break;
		}
	}
	return result;
}