As far as bottled water goes, spring water should work well. additionally, put about a half cup of water in the oven, in an oven proof container when you bake it helps.

Does anyone use bricks, or those brick sheets for baking on? I once had a pizza stone, made a huge difference!

BeeDee, that sourdough starter, it will last you forever if you feed it regularly won't it? Did you order it online?