Shrimp/Lobster Pita Pockets

1/2 pound cooked shrimp or lobster
    (or a combination of both)
1 stalk celery, chopped
1 green onion, chopped
1/4 cup plain yogurt
Pepper
Pita bread
Lettuce, shredded
1 tomato, diced
1/2 cup grated cheese

Combine the shrimp and/or lobster, celery and green onion. Fold in yogurt, then season with pepper. Line the pita bread with lettuce. Add the shrimp and/or lobster filling. Top with the tomato and cheese.