reference number or object numbers

So is there a tutorial on how to reference a cc object  for a  recipe like I wanted to use  a custom pumpkin to be used in the carving table how do I reference that object example 
 
<T n="ingredient_ref">*******<!--Pumpkin_White--></T>

or if I want to create a food stall how do I find the objects actual id

<V t="object_criteria">

<U n="object_criteria">

<V n="identity_test" t="definition_id">

<U n="definition_id">

<T n="actual_object">*****</T>

I m sure there is a tutorial out there but maybe I'm searching the wrong terms any info or help will be appreciated