looking for a friend in the United states

That is quite a general description, and New Jersey is a rather large place, especially if she was only living there for a short period of time and then moved. I hope that you find your friend, but I do not think that you will find her in this manner. You would do better trying to search for her on the Internet to find out whether or not she has an account on a social networking site, such as Facebook or MySpace.