Rose of Sharon Acres Tea Tree & Peppermint shampoo bar is my favorite. It keeps the scalp flakes to a minimum for me.
I would second the recommendation for Stirling's bath soap. Although I have also found that many tallow bath soaps work great. Mystic Waters makes another first rate shampoo bar as well, and long lasting.
I have only tried it once, and will be using it again tomorrow, but I have had a good experience with PAA's Sandalwood Shampoo Soap. I wish I had more curb feelers on the top of my head, but with the few I have, I enjoyed the PAA shampoo. With one one use so far, I can't recommend it, but it worked great the first time. I use it with my "Sandalwood" shaves - at least until I finish my other shampoo, then I may switch for good. Steve
I've been using Stirling for the past week with good results. I have, however, just received my order from Chagrin Valley, so I can now compare. The Stirling has reduced my scalp itching, but I seem to have just as much flaking.