General

LD OnLine
(from The Learning Project at WETA, Washington, D.C.)

ABCs of LD/ADD and LD In Depth list helpful and authoritative full-text articles.
Offers impressive depth and breadth on LD and ADHD topics, as well as links to other resources and a calendar of LD/ADHD conferences.

Organizations

Attention Deficit Disorder Association
"Focuses especially on the needs of AD/HD adults and young adults with AD/HD."

CHADD: Children and Adults with Attention-Deficit/Hyperactivity Disorder
"CHADD is the nation's leading non-profit organization serving individuals with attention-deficit/hyperactivity disorder (AD/HD)."
Objectivity Warning: CHADD receives substantial funding by the makers of Ritalin, which may influence their endorsement of this medication.

Learning Disabilities Association
"LDA strives to advance the education and general welfare of children and adults with learning disabilities."

National Center for Learning Disabilities
"The mission of the National Center for Learning Disabilities (NCLD) is to increase opportunities for all individuals with learning disabilities to achieve their potential."

Nonverbal Learning Disorders Association
Hard-to-find resources.
Also be sure to visit NLD on the Web for more extensive coverage.