Soak wood skewers in water for 20 minutes.
Cut lamb into 1-inch cubes. Toss with oil, garlic, paprika, cumin, oregano, salt and pepper; set aside for 20 minutes. Chop onion and bell pepper into 1-inch pieces. Thread onions, peppers and lamb onto skewers; brush with olive oil. Broil, grill over hot coals (or a hot gas grill), or sear in an oiled grill pan over high heat until lamb is charred on all sides, 8 to 12 minutes.
Squeeze lemon over kebabs; serve over warmed pita or naan.