Cook wild rice according to package directions. Drain; refrigerate 30 minutes or until chilled.
Meanwhile, in small bowl combine salad dressing, sour cream, salt, marjoram and pepper; blend well.
In large bowl, combine cooked rice, chicken, celery, bell pepper, mushrooms and onions. Add mayonnaise mixture; toss gently. Cover; refrigerate 2 to 3 hours to blend flavors.
Arrange lettuce on 4 individual plates. Spoon salad over lettuce. Garnish with tomato wedges and toasted almonds.