A great place for cat tails is in Hyde Park (MB) at the fountain. You can get upwards of six there at a time.
Night shade is a rare reagent you can sometimes get from deep mushrooms. You can get a recipe to transmute deep mushrooms to night shade. I not sure if you can get the recipe in MB or MS. I do know you can purchase it in CL.
Like nightshade, Bloodmoss is a rare reagent you get from red mandrake. You can also purchase a transmute recipe for that also.