Coriander seeds: are wonderful with fish and can be used whole or ground, if ground are being used grind a little with a pestle and mortar
Dill: has a great fresh taste that pairs perfectly with fish if you have a whole fish you could stuff it with fresh dill and butter
Lemongrass: this is a delightfully fragrant herb and great in Thai seafood soups
Parsley: makes a great bechamel sauce with cod
Tarragon: a great herb with fish particularly salmon and can be used in place of dill
Bay Leaves: a must for a Portuguese fish stew
Basil: is a key ingredient in tomato based dishes and would be a nice addition to a spicy tomato based seafood pasta
Cayenne pepper: a key ingredient to a seafood gumbo
Curry Powder: a must for any type of fish curry
Mustard: used lightly makes a great glaze for poached salmon