I always recommend that people pay for an initial consultation with an attorney who specializes in Family Law just to give them an understanding of the process, the courts and the mandatory rules. It will make it a bit easier to then review the pleadings on line that you can complete on your own, and also give you an idea of which facts the courts care about and which they don't. If his name is not on the birth certificate, Nevada law presumes that you already have primary physical custody. There can be a bigger picture to determining whether you should initiate any action. This cite will take you to the Family Law self-help Center and the forms necessary to begin a case if that is the route you go. http://www.clarkcountycourts.us/shc/index.htm
I agree with the answer provided by Attorney Kunin. Your first step should be to see a qualified family law attorney. I understand that money may be an issue, however many attorneys charge either no fee or a reduced fee for a consultation, and having a basic understanding of your options will be very helpful.
You may also wish to contact the Legal Aid Center of Southern Nevada or the State Bar of Nevada about your options for obtaining an attorney. Depending upon your income level, you may qualify for services through the legal aid center at no cost to you. Additionally the lega aid center offers classes on varies topics which may be helpful to you in handling your own case. As another alternative, the State Bar of Nevada offers a service known as the "reduced fee panel", under which they have attorney who are willing to accept cases as reduced rates which may be more affordable to you.
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