When asked for a spell, a person I met in a pagan chatroom said, "I would rather give someone a nuclear bomb than give a spell to a beginner and I would feel much safer."
At the time, I found it a bit funny and witty but later, after considering what he said, I had to agree with him. Some witches and/or pagans may disagree with me, and I acknowledge that they have the right to their own opinion, but I can't imagine giving someone a spell when I can never know how they will use it. I would not even give my best friend a spell not knowing how they will use it.
I am a firm believer that spells can be likened to prayers. It may be the Christianity in my background that makes me say that but to me spells are a way of asking the Goddess to do something for you in a specific way. My belief may not be others though. Some may use spells I have written to manipulate someone else or cause someone else's downfall for their own gain. I cannot take that responsibility. Besides, the outcome of a spell for me may be very different for someone else. When I "cast" a spell, I do it with a humble, beseeching heart that is devoted to my Goddess. I could not imagine giving my personal spells, my "prayers", to someone who may pervert them.
My dear friends, I do not mean to discourage you who are searching for the meaning of Wicca nor am I saying that you would do such a thing but to me, spells are very private things. Please bare me no ill will if you were searching for spells. I am sure that you will be able to find them somewhere else but before you think of casting a spell, learn the true meaning of the religion you are researching and are interested in. Strive to understand Wicca and its components. If you find a spell, study it piece by piece but do not think of casting it unless you are ready to take the responsibility for your actions.
Make sure the spell does not:
1) Go against the Wiccan Rede (Harm none do as ye wilt).
2) Result in the manipulation of someone else's free will.
3) Compromise your own judgement, morals, and feelings about what is good and what is not.
4) Require harming someone else or causing someone else to suffer.
There are more that should be on this list (^) but I do not have the space to write them all down.
If you have a more experienced person or group who you trust, ask them about their theories on casting someone else's spells or giving your spells to someone else and see what they say. Do not take my own rules as cast (pardon the pun) in stone. I invite and charge you to explore on your own to form your own theories on this subject. The glory of this religion is that it is based on a person's right to think for him or herself, SO THINK FOR YOURSELF. Learn, read, ask questions, and think for yourself and form your own conclusions.