Do i need an attorney and do I have the right to have this person arrested?

I observe that you need an attorney to send a cease and desist letter. The letter has to have some teeth in it.
Get the person's attention that you have rights and that you are willing to fight for your rights. Your attorney can best advise you about how to involve, if at all, the police authorities.

You might find my Legal Guide helpful "How to Choose A Lawyer For You"

http://www.avvo.com/legal-guides/ugc/how-to-choose-a-lawyer-for-you

You might find my Legal Guide helpful " What Do I Tell My Lawyer"

http://www.avvo.com/legal-guides/ugc/what-do-i-tell-my-lawyer

You need a lawyer. Check with a lawyer in your locale to discuss more of the details.

Good luck to you.

God bless.

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