One Step Checkout – show shipping methods after postcode entered

Would you like to show shipping methods of a one step checkout plugin after that a postcode is entered?

Go to the file app/design/frontend/base/default/template/checkout/onepage/shipping_method/available.phtml and replicate this file in your default interface/theme. Within the file, after (about line 31):

<p><?php echo $this->__('Sorry, no quotes are available for this order at this time.') ?></p>
<?php else: ?>

Add:

<?php
	$checkout = Mage::getSingleton('checkout/session')->getQuote();
	$billAddress = $checkout->getShippingAddress();
	$postcode = $billAddress->getPostcode();

	/* 13-10-2014 Added requirement to enter postcode before shipping */
	if (isset($postcode) && $postcode == "")
	{
	?>
	<p><?php echo "First enter your postcode before the shipping costs are calculated."; ?></p>
	<?php
	}
	else
	{
	?>

And close the else tag at the end. You can do this with countries, cities, etc. as well by changing the $postcode = $billAddress->getPostcode(); variable to:
$postcode = $billAddress->getCountry();

Good luck!