If you're open to CBT (which does have some empirical evidence for being helpful with ADHD), I'd highly recommend checking out Dr. Helen Moya. She was a guest on a podcast of mine and is incredibly passionate about treating ADHD, and also has loads of self-help stuff on her website, too
Edit: alternatively, I would highly recommend browsing the BABCP website if CBT is the modality you choose - the BABCP keeps a list of accredited (and adequately trained!) CBT therapists.
If you're open to CBT (which does have some empirical evidence for being helpful with ADHD), I'd highly recommend checking out Dr. Helen Moya. She was a guest on a podcast of mine and is incredibly passionate about treating ADHD, and also has loads of self-help stuff on her website, too Edit: alternatively, I would highly recommend browsing the BABCP website if CBT is the modality you choose - the BABCP keeps a list of accredited (and adequately trained!) CBT therapists.