Contact Dale at the Orvis shop in Richmond. Not only do they tie up a special fly for the shad run up the James, he is hands down an expert at the tactics. From what I remember of my time there, think heavy sinking lines out in the middle of the large navigable lanes. They come up in schools, and once your into one, just keep casting out. I think the VA DNR has a shad cam also, and I used to love sneaking a peak while at work and watching. It would be nothing for action for 5 or 10 minutes, then a school would come thru and the screen was filled. It was pretty neat, also got to play name that fish as everything else you could imagine would swim by, Musky, Gar, SM, etc.

Those Shad flies from what I remember had yarn bodies with a parachute like top and the yarn would pulsate in the currernt on the sinking line and drive the shad nuts. I just never had access to a boat to go try it.

Good luck!