Taking Charge of Adult ADHD by Dr Russel Barkley may be interesting for you. It has tests in it and talks about living with adhd as an adult. It's also pretty adamant about getting tested by the pros since you, of course, can't diagnose yourself, only test similarities with classic symptoms.
I'm undiagnosed myself btw, but have a lot of symptoms and have systematically ended up in communities where people are either adhd or autistic. Always thought it was a coincidence until a few years ago.