Some of the transcriptions of the Plano Cemeteries are available on the Tombstone Transcription Project of USGenWeb - www.usgenweb.com. Go to the Tombstone Transcription registry, Texas, Collin County. Also, the attached link with this message goes to a site what has the location of each cemetery, and availability of Collin County cemetery transcription books done in the early 1970's. I hope this gives you some leads.