Getting Started: Valuable Resources
In the early stages of committing to a strategy to improve and strengthen one's mental health, I have found that there are some easily accessible resources that have nuggets to full-on boulders worth of information and knowledge.
American Psychiatric Association
You can look up practice parameters/guidelines for various conditions. It can give you a road map to follow.
American Psychoanalytic Association
This is helpful to understand psychoanalysis. I use psychodynamic psychotherapy which is related to psychoanalysis.
American Academy of Child and Adolescent Psychiatry
A good resource for families with a child or children who is having mental health trouble. Look at their "Facts for Families" or "Practice Parameters".

National Alliance on Mental Illness (NAMI)
An excellent resource. Look up medications, find local support and learn more about mental health conditions.
Children and Adults with Attention Deficit/Hyperactivity Disorder (CHADD)
Learn more about ADHD. Get family training for AHDH.
The guide was last updated in 2013, but many of the principles are unchanged.