Completely agree with Memzak, but being ADHD myself, feel I need to post my two bits worth 
One other book I would recommend is called Delivered from Distraction. It’s basically the newer version of Driven to Distraction, written by the same guy ten years after he wrote Drive to Distraction, Dr. Ed Hallowell (who has ADHD himself). I’ve read both, and I must say that Delivered from Distraction was a lot more helpful to me, as a lot more about ADD has been discovered in recent years.
Also, sounds like you’ve been on quite a roller coaster, which is very typical of ADHD. At this point, I recommend getting properly diagnosed (if you have not done so already). In Dr. Hallowell’s book I mentioned earlier, he made a point about this which I think is a very good point, be careful about which doctor you see about this. Family doctors will try their best, but it’s not their field, so a psychologist would be good. Secondly, do some research and see if you can find a doctor who treats people, not patients (in other words, doctors who will want to spend time really getting down into your personal roadblocks and not just prescribe meds, give a few tips, and shoo you out the door). Admittedly, those kind of doctors can be hard to find, but if you can find one who will at least work with you a little bit, you can substitute the rest via community support (like here ). One more thing, for myself and for other’s I’ve known, medication is one of the most substantial interventions you can get, so if a doctor wants to prescribe you medication, I suggest accepting the prescription, and then research it on your own before you actually get it filled, but please do not dismiss it out-of-hand as a valid aid. Educate yourself with reputable sites first about the medications suggested (a very good analysis of the variant medications out there is in that book I mentioned earlier).
Also, just like Memzak said, educate yourself! I cannot stress that point enough. Just so you know though, I highly doubt you will have to push to educate yourself once you get started as it will bring a whole new world of understanding about yourself, which will likely make you want to know more. Make the effort to start educating yourself. If you cannot take the time to read a book (like you already hate me for writing such a long post, lol), then get it on CD or MP3 and listen to some of these books while you’re driving your car or out for a walk or just at home occupying yourself.
Anyhow, I hope this helps you a great deal 