Do I have to buy a bunch of Witchcraft supplies like candles, paper, fabric, etc? Also, if I don’t have these things will the spells still work?
Wiccans believe in the unified spiritual essence of the universe from which the Goddess and God emerged.  No one but yourself can decide when you will become a wicca. Your dedication does not depend on how many “things†you have, but how you use them.
Listen to your inner voice. If you feel that you don’t need all this “stuff†to make you a good Wiccan, you probably don’t. There are no right or wrong answers in our belief systems. What seems right to you, does not hurt any other living soul and fills you with peace is probably the best choice for you.
When you decide to follow the Wiccan traditions, its time to perform a dedication ritual. This ritual is yours and you alone will decide how you want to mark this milestone in your life. You are dedicating yourself to the Craft and to a life that is in harmony with nature and everything around you. This commitment is to yourself as well as to the Divine.
Many people have trouble concentrating on a ritual or spell. Sometimes it is necessary to have several “items†that will hold our concentration. Most of the wicca supplies serve that need. A candle uses its aroma and flame to mesmerize us while an incense stick fills our sense and thoughts with peace.
This religion discourages the use of unnatural substances. The moon, Flowers, sticks found in the yard, fire (usually from candles), natural aroma from incense etc  are used for rituals. Mirrors, oils, water, etc are also used.
Most importantly we use our mind to become one with nature. Meditation on the love that surrounds us, our breath that sustains our life and the chakras or energy centers of our body are usually points of focus during our commune with nature. The five elements of nature which comprises of earth, air, fire, water and wood will essentially  fulfill your demands for “wiccan supplies†in the highest sense.
The goal of this path to the Divine is to raise, channel and direct energy so that our circle is complete. Ultimately, you must do what feels right to you.