You can put most plastic water bottles in a dishwasher, as long as they are away from the heating element.  Another approach is to soak bottles in warm, soapy water or water with added lemon juice or baking soda.  If you have a deep stain, pour one cup of water and one tablespoon of bleach into the bottle to soak.  If you have an odor that is strong and will not go away, wrap a charcoal briquette in a newspaper and put it in the bottle, secure the cap and let it sit for a few days.  Stickers and price tags can be removed from bottles by soaking in hot water or rubbing baby oil on the area, being careful not to scratch the bottle in the process.  If you put your bottle in the freezer, be sure to leave plenty of room for expansion.