PHP Looping through results ( within a loop ) . I am stuck.

I am making a Nav bar, it is simple the letters A-Z representing first letter of customers:

# A B C D E F G H I J ...

I have 3 classes that style the TD based upon whether the letter has a customer.

1. projectsNavTdOn  = The active letter ( for instance if we click 'A' the 'A' is highlighted )
2. projectsNavTdOff = No customers with this letter
3. projectsNavTdOffwithContent = There is a customer in this letter, but we are not on that page.

Here is a screenshot, that will help you understand better:

http://img235.imageshack.us/img235/296/navig5.jpg

In this case, we are letter A ( it's highlighted ) , but we also have customers in the Letter C.

Now my code. I am stuck. Basically I need to loop through both , don't I???

Thanks!

// @param $Letter = Active Page Letter

function printCustomerNavBar($Letter){

      global $db, $_DB_name, $_DB_host , $_DB_user  , $_DB_pass, $_TABLES, $_USER;
      
       // Each iteration should contain the following:
      // <td class="projectsNavTdOff" id="td_#" onclick='location.href="customer.php?letter=%23"'>#</td>
      //<td style="width: 3px; margin-left: 3px;"></td>
      
      $alphabet = explode('','#ABCDEFGHIJKLMNOPQRSTUVWXYZ');
      
      $sql = "Select upper( Left( customers_name, 1)) AS first_letter
                  FROM customers
                  WHERE customers_users_id = {$_USER['masterId']}";
                  
      $result = $db->query($sql);
      
      /* Loop Through Results */
      for(var $i=0; $i<count($alphabet); $i++){
      
            while ($row = $db->fetchNextObject($result)) {
      
                  
            
            }      
            
      }
      
}