How to get shipping address by shipping address id?

You could use the order_address object to get the shipping address:

 $address = Mage::getModel('sales/order_address')->load($shippingId);
// $shippingId is the id you get from order object.
$custName = $address->getName();
$custAddr = $address->getStreetFull();
$region = $address->getRegion();
$country = $address->getCountry();

or use

print_r(get_class_methods($address)); 

to see what are the methods that can be used on the address object ($address).

hope it solves your prob :)

To get the Address from an order object you could simple do $order->getShippingAddress()

Assuming

$order_id = 123; // put your order id here
$order = Mage::getModel('sales/order')->load($order_id);

Then

$address = $order->getShippingAddress();
$custName = $address->getName();
$custAddr = $address->getStreetFull();
$region = $address->getRegion();
$country = $address->getCountry();

Shathish has given you a nice and correct answer.

However, you can use the singleton method and a query:

$shimnetId = "1"; // use your shipment id: 

$read = Mage::getSingleton('core/resource')->getConnection('core_read');

$query = "SELECT * FROM sales_flat_order_address WHERE entity_id='".$shipmentId."'";

$results = $read->fetchAll($query);

var_dump($results);

sales_flat_order_address contains both the billing and shipping address.

Hope it will work for you.