I'm Alicia, I'm happy to help you today.
While medication is helpful for many people with ADHD, it is by no means always necessary, and there are several self-help strategies you can use to help yourself stay focused and to help control your symptoms.
Cognitive-behavioral therapy (CBT) can help - there have been a few studies that show that CBT techniques are useful for adult ADHD - although many of these studies used CBT as an adjunct treatment to medication. Cognitive-behavioral therapy is generally a short-term form of treatment, where you work with a trained therapist who helps you develop and implement a concrete, goal-oriented treatment plan. Since it sounds like you are doing a pretty good job managing your symptoms on your own, you might consider consulting a cognitive-behavioral therapist for a few sessions to get some specific tips for your situation.
As a side note, you might be interested in reading the results of a study that was done using CBT (and medication) on adults with ADHD - keep in mind that CBT techniques can be helpful without medication. http://www.sciencedaily.com/releases/2010/08/100824161434.htm
CBT techniques can help you cope with distractions, help you maintain concentration, keep yourself organized and help you focus on your goals.
If you are interested in learning more about CBT and finding a therapist, you might wish to look at this website:http://www.babcp.com/Default.aspx
Additionally, this article from Help Guide describes many useful self-help tips for adults with ADHD:http://www.helpguide.org/mental/adhd_add_adult_strategies.htm
Certain alternative medical techniques have proved useful in preliminary studies, so if you're interested in pursuing a holistic route, you might want to review this information:http://www.mayoclinic.com/health/adult-adhd/ds01161/dsection=alternative-medicine
Some diets (elimination diets that avoid certain foods, for example) have been found to be helpful, but if you are interested in pursuing this route, I'd advise you to consult a licensed nutritionist before making any dietary changes.
I hope that is helpful. Please let me know if you need additional assistance.