Put flour, herbs / spices and salt into a large bowl and mix.
Put lemon / lime juice in to a small bowl. Dip fish into juice and then into flour mixture until lightly coated.
Heat oil in frying pan. Add coated fillets. Sauté for 2-3 minutes on each side until cooked. Remove from pan, cover to keep warm.
Clean and dry pan. Put over medium heat. When hot, add corn tortillas and cook for approximately 30 seconds and each side.
Put salsa and sour cream in a small bowl and mix.