(1) Olive Oil Source: http://www.oliveoilsource.com/
This is a US web site where you can find a lot of informations about olive tree growing.
On the left of the home page there are many categoried links and particularly at the bottom there are some links named 'Olive Facts'. They conduct you to some pages about the olive tree taxonomy, crop farming and history. Besides there are some useful definitions about oil commercial categories (Virgin, Extra Virgin, etc.) and informations about olive-oil production.
(2) The Australian Olive Association: http://www.australianolives.com.au/
(3) Zaitun.org - Palestinian Olive Oil: http://www.zaytoun.org/
Zaitun is the arab word for olive. In this web site you can find informations to buy palestinian olive oil all over the world. Besides are informations about Palestine.