The DSM IV Criteria for ADD: A Closer Look

Compares the symptoms of ADHD/ADD with descriptions of the types to see which personalities are at risk for misdiagnosis.  A highly detailed, cited look at the issue of type and ADHD/ADD.  The rest of the website also deals with this question and is recommended. 
If you have ever wondered whether ADHD/ADD is type, then this is a good place to begin.