Great Naspinsky, I didn't know that functionality. However, How can I specify the another specific id's inside the click function? if I use $(this) is great for "group_link_" but I need to do specific things for another id's as you can see below:
Here is the real code which I have to replicate "i" times. This code is working for i=0. The specific id's for i=0 are: group_link_0 - group_content_0 - contact_list_0 And I should do the same for group_link_1 - group_content_1 - contact_list_1....etc.
        $("#group_link_0").click(function() 
    {
        $("#group_content_0").empty();
        $().SPServices({
          operation: "GetUserCollectionFromGroup",
          groupName: $("#group_link_0").text(),
          async: false,
          completefunc: processUsersGroups
       }); 
       function processUsersGroups (xData, status)
       {
            var i = 0;
            var email_user="";
            $("#group_content_0").append("<ul id=\"contact_list_0\" class=\"contact_list\"><div id=\"paginator\" class=\"paginator_accordion\">");
            $(xData.responseXML).find("[nodeName=User]").each
            (
                function()
                {   
                    if ($(this).attr("Email")!="")
                    {
                        email_user=$(this).attr("Email");
                    }
                    else
                    {
                        email_user="<i>Not Available in Active Directory</i>";
                    }
                    $("#group_content_0").append("<li class=\"contact\"><div class=\"user\"></div><div class=\"user_name\">"+$(this).attr("Name")+"</div><div class=\"mail\"></div><div class=\"user_mail\">"+email_user+"</div><div class=\"thick\"></div><div class=\"minus\"></div><div class=\"plus\"></div></li>");
                    i++;
                }
            )
            if(i==0)
            {
                $("#group_content_0").append("There's no users available in this group");
            }
            else
            {
                $("#group_content_0").append("</div></ul>");
            }
       }
       $(function(){ $("#paginator").pagination(); });   
    }
    );