Dead Man's Journey by Jay W Sharp. Narrative and pictures of various ruins along the trail.
Official El Camino Real de Tierra Adentro National Historic Trail Website from the National Park Service (NPS).
The Comprehensive Management Plan/Final Environmental Impact Statement for El Camino Real de Tierra Adentro National Historic Trail contains maps of the trail. They are attributed to the BLM.
The NPS code for this trail is ECLA.
The NPS has a detailed vector of the trail with this online map viewer.
The BLM at some point had commissioned an online interpretive Flash application, with comprehensive GIS data included. See screenshots.