$client = new SoapClient('
magentohost/api/soap/?wsdl');
// If somestuff requires api authentification,
// then get a session token
$session = $client->login('apiUser', 'apiKey');
$result = $client->call($session, 'catalog_product.list');
var_dump($result);
// If you don't need the session anymore
//$client->endSession($session);
Как то так.