Combine first 8 ingredients in large bowl. Mix in shrimp. Marinate at room temperature 1 hour or in the refrigerator 5 hours,stirring occasionally. Prepare barbecue with medium hot coals.
Thread shrimp on narrow skewers.
Grill until just opaque,about 2 minutes per side. Line platter with spinach. Arrange skewers on platter. Garnish with lemon and serve. Makes 8 servings.