The Way of St James can be split into 2 parts; the Via Podiensis from Le Puy-en-Velay to Saint-Jean-Pied-de-Port and the Camino Francés which continues on to Santiago de Compostela.
The two parts of the route are shown below together with a Google Earth file. I did NOT however use a GPS myself! Seeing where the road lead was much more fun anyway.
Via Podiensis
Download Google Earth KMZ File
Camino Francés
Download Google Earth KMZ File