Яндекс Маркет.

// Создаём новый документ.
// Первый параметр конструктора - версия XML, второй - кодировка
$doc = new DOMDocument('1.0');

$doctype=DOMImplementation::createDocumentType('yml_catalog SYSTEM "shops.dtd"'); // creating real doctype
$doc_feed=DOMImplementation::createDocument('', '',$doctype);

$doc_feed->encoding='windows-1251';

$elem_rss = $doc_feed->createElement('yml_catalog');

$elem_rss->setAttribute('date', date("Y-m-d h:i"));
 
$doc_feed->appendChild($elem_rss);

$elem_shop = $doc_feed->createElement('shop');
$elem_rss->appendChild($elem_shop);

$elem_shop_name = $doc_feed->createElement('name',"ГПМ");
$elem_shop->appendChild($elem_shop_name);

$elem_shop_company = $doc_feed->createElement('company',"Продажа грузоподъемных механизмов");
$elem_shop->appendChild($elem_shop_company);


$elem_shop_url = $doc_feed->createElement('url',"http://***.ru/");
$elem_shop->appendChild($elem_shop_url);



$elem_currencies = $doc_feed->createElement('currencies');
$elem_shop->appendChild($elem_currencies);

$currencies=$doc_feed->createElement('currency');
$currencies->setAttribute('id', "RUR");
$currencies->setAttribute('rate', "1");
$elem_currencies->appendChild($currencies);


$elem_categories = $doc_feed->createElement('categories');
$elem_shop->appendChild($elem_categories);

$i=0;
$id_c="";
$sql=mysql_query("SELECT * FROM Menu WHERE parent_id=51");
while($row=mysql_fetch_assoc($sql))
{
	$categories=$doc_feed->createElement('category',$row['Name']);
	$categories->setAttribute('id', $row['id']);
	$elem_categories->appendChild($categories);

	$id_c.=$i==0?"'{$row['id']}'":", '{$row['id']}'";
	$i=1;
}

$elem_offers = $doc_feed->createElement('offers');
$elem_shop->appendChild($elem_offers);

$sql=mysql_query ("SELECT *,Equipping.id as id_e FROM Equipping JOIN product ON Equipping.article=product.art WHERE Equipping.id_category IN ({$id_c}) ");
while($row=mysql_fetch_assoc($sql))
{
	$offer=$doc_feed->createElement('offer');
	$offer->setAttribute('available', "false");
	$offer->setAttribute('id', $row['id_e']);
	$elem_offers->appendChild($offer);

	$row=array_map("trim",$row);
	$row=array_map("strip_tags",$row);
	$row=array_map("htmlspecialchars",$row);

	$price=round(($val['i']*$row['currency']*$set['nds']*$set['doh']),2);

	$offer->appendChild( $doc_feed->createElement('url', "http://***.ru/category/{$row['id_category']}/equipping/{$row['id_e']}") );
	$offer->appendChild( $doc_feed->createElement('price',$price) );
	$offer->appendChild( $doc_feed->createElement('currencyId', 'RUR') );
	$offer->appendChild( $doc_feed->createElement('categoryId', $row['id_category']) );
	$offer->appendChild( $doc_feed->createElement('name',$row['name']) );
	$offer->appendChild( $doc_feed->createElement('description', $row['pol_info']) );
	$offer->appendChild( $doc_feed->createElement('sales_notes',"Доставка товара производится течение 3-4 недель после прихода денег на наш счет.") );

}
// Сохраняем документ в файле sample.xml
$doc_feed->save('sample.xml');