How to LEFT JOIN a SubQuery?

[resting]

What I'm doing here is to add a column (named outOfStock) to my existing table prod_info.

I used this query to generate my outOfStock table.

SELECT prod_id, XS, S, Splus, M, L, XL FROM prod_info AS outOfStock WHERE
     XS    IS NULL &&
     S     IS NULL &&
     Splus IS NULL &&
     M     IS NULL &&
     L     IS NULL &&
     XL    IS NULL 

Then I used a LEFT JOIN to combine them.

SELECT * FROM prod_info LEFT JOIN (
  SELECT prod_id, XS, S, Splus, M, L, XL FROM prod_info AS outOfStock WHERE
     XS    IS NULL &&
     S     IS NULL &&
     Splus IS NULL &&
     M     IS NULL &&
     L     IS NULL &&
     XL    IS NULL
) ON prod_info.prod_id = outOfStock.prod_id 

It prompts me this error message:

Every derived table must have its own alias.

I'm totally a goner at subqueries and joins. How does it mean and how do I achieve what I want?

Oh yes, please recommend some really simple reading on joins and subqueries. Most that I'd seen are quite difficult to understand.