I was doing some internet reading a few days ago and came across an interesting division of people with ADD with or without hyperactivity.
This site splits into 6 types.
http://www.add-adhd-help-center.com/add_types_main.htm
Here's a summary:

Classic ADHD characteristics:
_ Inattentive.
_ Hyperactive.
_ Easily distracted.
_ Disorganized.
_ Restless.
_ Impulsive.

Inattentive characteristics:
_ Easily distracted.
_ Disorganized.
_ Low energy level.
_ Easily bored.
_ Short attention spans for tasks that are not interesting or that are difficult.
_ Daydreams often.
_ "Head in the clouds."

Overfocused characteristics:
_ Worries excessively, even over unimportant matters.
_ Oppositional..
_ Arguementive.
_ Compulsive.
_ Has difficulty shifting from one activity to another.
_ Always wants his way.
_ Is rigid and uncompromising.

"Temporal Lobe" Characteristics:
_ Easily irritated or frustrated.
_ Aggressive.
_ Dark moods.
_ Significant mood swings.
_ Impulsivity.
_ Prone to fights and acts of violence.
_ Defiant toward authority figures.
_ Can display anti-social behavior.
_ Learning problems and bad handwriting common with this type.

"Limbic" Characteristics:
_ Inattentive.
_ Chronic sadness.
_ Often negative or apathetic.
_ Low energy levels.
_ Feelings of helplessness, hopelessness or low self-worth.

"Ring of Fire" Characteristics:
_ Oppositional behavior.
_ Irritability.
_ Excessive talking.
_ Temper problems.
_ Extreme moodiness.
_ Distractibility.
_ People with this type tend to be sensitive to sounds.

I've never come across ADD divided this way before. I was reading ADD and Creativity and they divided ADD into 3 types (but I think it might have been singling out add without hyperactivity...) and I couldn't figure out which one I was more. I'll have to find the book again but I think it was divided into something like "Outwardly Expressed ADD", "Inwardly Expressed ADD", and "Highly Structured ADD". But I know I shared things in common with all three, especially outwardly expressed and highly structured.

I went to the site where they divided it into 6 and copied and pasted the info into a word document. I highlighted the things that fit me, and yet, again, I'm all over the map still lol.

I'm posting this in hopes people might benefit from the info, but also out of curiosity for what has been studied in types of ADD. Does anyone know anything else about ADD types?