Bread should be unsliced.
Preheat oven to 350. Cut a hole about 5" in diameter in the top of the bread. (If you wish, make a decorative zigzag pattern.) Reserve crusty part to make top for loaf. Scoop out most of soft inside portion and save for another purpose.
In skillet, saute green onions and garlic in butter until onions wilt. Do not burn! Soften cream cheese and cut into small chunks, then place in medium-sized bowl; add onions, garlic, sour cream, and Cheddar. Mix well. Drain non-marinated artichoke hearts and cut into quarters. Fold in artichoke hearts.
Fill hollowed-out bread with this mixture. Replace top of bread and wrap in a double thickness of heavy-duty aluminum foil. Bake for about 1-1/2 hours.
Remove foil and top of bread and serve, using thin slices of warm garlic bread as dippers.
Note: The best part of this dish is when the dip is gone and all you have left is the bread, which is soaked in all those delicious ingredients. Just break the bread up and pass it around!