WooCommerce – Additional tabs between tyhe product description tab and the review tab

You can add this function to create a custom tab. 
There is more information that can be found here http://docs.woothemes.com/document/editing-product-data-tabs/
 
If you are looking for a plugin for this you can find it here. http://www.woothemes.com/products/woocommerce-tab-manager/

add_filter( 'woocommerce_product_tabs', 'woo_new_product_tab' );
function woo_new_product_tab( $tabs ) {
	
	// Adds the new tab
	
	$tabs['test_tab'] = array(
		'title' 	=> __( 'New Product Tab', 'woocommerce' ),
		'priority' 	=> 50,
		'callback' 	=> 'woo_new_product_tab_content'
	);

	return $tabs;

}
function woo_new_product_tab_content() {

	// The new tab content

	echo '<h2>New Product Tab</h2>';
	echo '<p>Here\'s your new product tab.</p>';
	
}