How do I get custody of my child if she is in a different state.

My ex bribed to sign over full custody to him to get away from him. He was abusive and staying around the same area was not an option for me. My daughter lives with his parents in Texas. My fiance and I live in Nebraska and we would like to know if we could file for custody in Nebraska or would have to go down there and file. We're afraid that if we file there he will have more pull on the judge than we do. - Is this your question? Add additional information