Here are some websites that you may find useful:
Resources for individuals interested in or with assistance dogs:
American's with Disabilities Act Service Dog Information
American Veteran's Affairs Guide and Service Dog Information
International Association of Assistance Dogs Partners
International Guide Dog Federation
Canadian Guide Dog & Assistance Dog Schools
Resources for animal assisted interventions and therapy dogs:
Animal Assisted Intervention International
International Association of Human-Animal Interaction Organizations
Pet Partners - Therapy Pets and Animal Assisted Activities
Resources for ADI member organizations and individuals interested in dogs working in the legal system.
Courthouse Dogs Foundation website
Resources for assistance dog organizations:
International Working Dog Registry
Taproot Foundation
*services available in the US, UK, EU, and India
Resources to find a professional private dog trainer:
UK Association of Pet Dog Trainers
US Association of Pet Dog Trainers
International Association of Canine Professionals
United States Department of Veterans Affairs