mixing php and javascript to do automatic subtotals on a form

[vgfwweb]

I've got a table / form that's being built using php, pulling data out of a mysql database.
what i need it to do is:

column 1, show the item image
column 2, pull the item name from the database
column 3, pull the item cost from the database
column 4, get the quantity from the user
column 5, automatically show a subtotal, cost * quantity

bottom of the table - automatically calculate total

what i've got so far:

PHP Code:

<?php
mysqli_select_db($wowcalc, $database_wowcalc);
$query_getitems = "SELECT * FROM items";
$getitems = mysqli_query($wowcalc, $query_getitems) or die(mysqli_error());
$row_getitems = mysqli_fetch_assoc($getitems);
$totalRows_getitems = mysqli_num_rows($getitems);
?>
<form name="wowcalc">
<table width="800">
<tr><td>Image</td><td>Item Name</td><td>Item Cost Each</td><td>Quantity</td><td>Subtotal</td></tr>
   <tr><td colspan="5"><hr width="800px" /></td></tr>
    <?php
     do { 
     ?>

      <tr>
        <td><img src="images/<?php echo $row_getitems['image_name']; ?>"/></td>
        <td><?php echo $row_getitems['item_name']; ?></td>
        <td><?php echo $row_getitems['item_cost']; ?><input type="hidden" value="<?php echo $row_getitems['item_cost']; ?>" name="cost" /></td>
        <td><input type="text" name="quantity" size="10" /></td>
        <td></td>
    </tr>


      <?php } while ($row_getitems = mysqli_fetch_assoc($getitems)); ?>
</table>
</form>

unfortunately, I don't know javascript, and I havent had any luck finding anything like what I want to do. any help would be greatly appreciated.

Mike Roberson