The key to any custody battle is DOCUMENTATION (see http://www.deltabravo.net/custody/tips1.htm for Tips on Keeping Documentation).
You need to keep an accurate record of every missed visit, every communication with the X or the child, and every attempt to visit/contact/locate the child. There is a Parenting Time Tracker spreadsheet for Excel available at http://www.deltabravo.net/custody/tracker.htm
You need to get copies of the School and Medical Records of the child (see http://www.deltabravo.net/custody/access.htm for an article listing the statutes for each state on access to your childs records). Look in these records for evidence of a lack of proper parenting (many missing school assignments, poor attendance, poor overall performance) and for evidence of abuse (discipline problems in school, repeated trips to the doctor with unusual injuries, etc.).
Read the report Family Wars, The Alienation of Children at http://www.vev.ch/en/lit/alienati.htm or from the FRTC PAS Information Archive at http://www.deltabravo.net/custody/pasarchive.htm This report lists specific alienating behaviors to look for and to document.
There are a lot of other resources at the FRTC website, http://www.deltabravo.net/custody Check it out!