Here you will find many useful materials on organic accreditation.

IFOAM Training manual for IOAS systems-Useful and informative preview for the document available in the bookstore.  the IOAS system is working worldwide with the IFOAM Basic standard for organic accreditation. 

The website of the International Organic Accreditation Services, where you will find information about IFOAM accreditation and ISO 65 accreditation by the IOAS