Retrieving All Items

I have all of my items under List -> Website -> Items. For my PHP script, I need to grab all of these item internalIDs, Name & Description, and fill them into an array. I have the follow code, which allows me to grab the item name by using the internal id, but is there a way to grab all items at once (instead of individually by id)?

[PHP]$filter = new nsComplexObject('ItemAvailabilityFilter');
$recs = new nsComplexObject('RecordRefList');
$recs->setFields(array('recordRef' => new nsRecordRef(array('internalId' => $_GET['id']))));
$filter->setFields(array("item" => $recs));

$nsGetItemAvailabilityResult = $myNSclient->getItemAvailability($filter);