WHO DO YOU SUBPOENA FOR CELL PHONE, INTERNET AND ELECTRONIC RECORDS?
In family court, most - if not all - of these records are relevant to your case because they are admissible or could lead to admissible information - credit card use, gaming, gambling, phone records, uncontrolled Amazon spending, who your soon-to-be ex is associating with , photographs, etc., are all telling.
But, how do you get these records? It's unlikely the other side will volunteer them.
If you are not the primary account holder, such that you cannot access/print/retrieve phone records for your account, you should issue a subpoena to the appropriate phone service provider. Be warned, however, that the process can be cumbersome and expensive: lots of people going through lawsuits every day seek out phone records, and these providers are chronically backlogged in responding to subpoenas. That is, if they can respond at all. For some processes, you will need a court-issued subpoena, and perhaps a warrant. Some providers, notably FaceBook, will decline to respond absent special procedures unique to the provider, as well. To get you started, seek out the appropriate contact information, including the name and phone number for the provider's legal counsel, at the Internet Service Providers List, or the ISP List.
You can learn more here: http://www.search.org/resources/isp-list/