sideBlinded,

Welcome to the club of older adults dx'd with ADD. I am 43 and although I had the dx as a child, I did not have services or treatment. It wasn't until two years ago that I began seeing a pdoc and after reviewing my childhood records, he came to the conclusion that my ADD never went away.
Anyhow, as long as you are alive and involved in life you have a reason to understand your diagnosis better and seek ways to improve your life. I've heard a lot of good things about a brain training site called Lumosity. Their site focuses on improving memory and attention. They do charge but from what I've heard it's well worth it. I'm sure there are other sites similar to them that don't charge. If computer brain training doesn't appeal to you maybe doing things at home such as card games, puzzles, or two player games to keep the brain juices flowing and improve memory and concentration.
What ever you decide, just know that you have many years to go. Make them good ones.