Heat a skillet to medium high heat, or heat a grill.
Mix together smoked paprika, garlic powder, onion powder, cayenne pepper, oregano, salt, and black pepper in a small bowl.
Rub both sides of your tuna filets. Once skillet or grill is very hot, add the oil to the pan (if using grill no need to use oil). Sear for only 1-2 minutes per side, so the top is blackened and the middle is still pink and rare.
Now make your salsa. Stir together peaches, red onion, cilantro, and juice of half a lime.
Slice your tuna, and spoon salsa on top. Squeeze remaining lime juice over tuna, and salt to taste.