you can change the order the categories to products are displayed by adding an order by clause to the recordset.
the product results page is already set to order the products by the product name:
$query_WADAProducts = "SELECT * , coalesce((select ps3_productoptions.GroupingID from ps3_productoptions WHERE ps3_productoptions.ProductID = ps3_products.ProductID limit 1),ps3_products.ProductID) AS GroupingID FROM ps3_products WHERE ProductLive = 1 GROUP BY GroupingID ORDER BY ProductName";
but you could change this to order by another column if you like.