I have been dealing with this myself for a few years. Here is what works for me.
1. Plenty of exercise.
2. Cut out soda, unrefined sugar and corn syrup.
3. Take plenty of Omega-3 fatty-acids. (For kids I use a product called "Coromega" from Drugstore.com. Orange Flavor Packets can be added to many foods and tastes like orange yogurt)
4. Nuerofeedback! Look for this in your local phonebook. This type of therapy is new, but becoming very popular. Think of it as training for your son's brain.
5. Be aware of the situations that make ADD worse.
Good luck
This is good advice and worked for my second son. We put him on a multi vitamin with omega (attend formula) and it worked wonders. We also made sure he got plenty of rest. Parents fall into the trap that they have so much energy and never get tired. My son and daughter get hyper the more tired they get.
The son who is 8, sleeps 10 hours a night. Our 4 year old daughter sleeps 9-10 hours plus a 1 hour nap in the afternoon. The more rested they are, the more control and focus they have. But the vitamins and reduced carbs (sugar, corn syrup, crackers, etc) really made a difference.