If I have a court order to see my child and the mother has not let me or my family see the child and moved and we don't know where she lives what kind of action can I take?

Go to court and have them drag her in on contempt or parental kidnapping charges.

How long ago did she move ?

If you have a court ordered visitation schedule, and the mother moved without permission of the court and without informing you of her current whereabouts, then she is guilty of parental kidnapping.

You can go back to the court that issued the support order and ask that a warrant be issued for her arrest.

However, this only means that, if you can find her or she gets picked up on another charge (a speeding ticket or more) then she can be arrested. But the police are not likely to look for her.

You can hire a PI to find her, then go to the police where she lives now to arrest her. You can talk with her family and tell them that if they have contact with her that they should urge her to give herself up, because if she is caught she can lose custody of the child.

But if she goes underground and is careful, you may never find her. BTW, how old was the child when she left?