Thank you to all who responded regarding obtaining text message transcripts. What I gathered is that it depends on the judge whether or not they can be used in court- most leaning toward "no." Traditionally, a judge would only accept transcripts provided by the phone company.
Also, anyone needing legal help can be directed to the MeL Legal Help Gateway at
http://www.mel.org/legal. Patrons can also visit the state law library's page at
michigan.gov/lawlibrary. There is a listing of their services on their site.