OrderAdd:

$arFields = array(
   "LID" => "en",
   "PERSON_TYPE_ID" => 1,
   "PAYED" => "N",
   "CANCELED" => "N",
   "STATUS_ID" => "N",
   "PRICE" => 279.32,
   "CURRENCY" => "USD",
   "USER_ID" => IntVal($USER->GetID()),
   "PAY_SYSTEM_ID" => 3,
   "PRICE_DELIVERY" => 11.37,
   "DELIVERY_ID" => 2,
   "DISCOUNT_VALUE" => 1.5,
   "TAX_VALUE" => 0.0,
   "USER_DESCRIPTION" => ""
);

// add Guest ID
if (CModule::IncludeModule("statistic"))
   $arFields["STAT_GID"] = CStatistic::GetEventParam();

$ORDER_ID = CSaleOrder::Add($arFields);
$ORDER_ID = IntVal($ORDER_ID);