I have always struggled with ADD, not ADHD. But I have very similar problems. I find that coffee and repeating everything I hear back to myself in my head work best (short term) without going back to ritalin.

Although if I ever start a new job or something is going on where I really need to focus I need something to help. You don't have to take ritalin, but any OTC stimulant can work just as good if you find one that is just right for you. I like to use burn2 extreme if I'm going to be in a long boring meeting that is very important to stay focused in.

Play around with some (hydroxycut, xenedrine...) and only take it when you know you will need to stay focused. This is just the best way I have learned to deal with it but everyone is different.