These are the top books (and other items) that I have on my bookshelf and use on a regular basis for reference. I recommend them all.
Essential Reading
Essential Wiccan Tools
Earth
The most powerful protection crystals I have known are double terminated Herkimer Diamonds. These come from upstate New York. You can also find double terminated quartz from Pakistan, Arkansas, and the Himalayas. All stones have beneficial aspects to them. Rose Quartz to me is one of the best universal healing stones.
Air
I generally only burn pure un-adultered natural items and use high-end essential oils for all anointing.
Fire
I prefer 7 day unscented candles in glass for my altar and natural ceramic censer burners for incense.
Water
the vessel holding water on my alter is a carved agate stone bowl. Any natural object, whether, crystal, rock, metal or glass is fine. I like things to be in blue or green or silver for the water element. Steer clear of warm colors or brass goblets.