Combine first 5 ingredients in a large bowl. Cover and refrigerate.
Combine juice, oil, 1/4 teaspoon salt, 1/4 teaspoon pepper, and garlic, stirring with a whisk.
Heat a large nonstick skillet coated with cooking spray over medium heat. Sprinkle salmon with 1/4 teaspoon salt and 1/4 teaspoon pepper. Add fish to pan; cook 9 minutes or until fish flakes easily when tested with a fork, turning once. Combine arugula mixture and juice mixture; toss well to coat. Place 1/2 cup herb salad on each of 6 plates; top each serving with 1 fillet. Serve with lemon wedges.