Printing information - printernational.org

While researching something online, I ran across the website printernational.org, which includes the following statement of purpose:

Printernational offers information and tutorials about all aspects of graphic and print design, illustrator, photoshop, indesign and everything related to it. We also offer information on paper sizes, formats and design standards for working for print.

Comprehensive, helpful (at least to a novice like me), and recommended.