I make these quite often, my wife and I love them.

I fry my fish in the Louisiana New Orleans style fish fry batter for the fish tacos. Its a bit lighter with a hint of lemon.

For the sauce mix the following ingredients up.
1/2 cup helmans mayo
1/2 cup plain yogurt
1/2 tsp dried oregano
1/2 tsp dried cumin
1/2 tsp dried dill weed
1 tsp minced capers
1 tsp cayenne pepper
1 lime juiced
1 jalapeno minced (can use less to lessen the heat)

I then just warm up some flour tortillas, smear a bit of the sauce across the bottom of the tortillas, throw on a few chunks of crappie, toss on some coleslaw and bit of cilantro. You are now in crappie taco heaven. The sauce is great, I like it a bit spicy and the way the heat slowly comes on is nice. It doesn't hit you hard up front.