Huck, Some five years ago I wrote to the archivists of the Vatican library to find out about holy pictures of Mary Magdalene, that were prior to printing presses, ostensibly for the tourist trade of pilgrims. In the correspondance that followed I was told that indulgences, holy pictures,and single page documents were wood engraved on vellum, parchment and stiffened linen cloth. Part of the correspondance I have copied out for you below. It was then I found out about the illuminators guilds. Maybe it is an avenue for you to follow, because the illuminators were very powerful and paid by the church, so they protected their trade. The archivist seemed to think that the first holy pictures, by woodblock on stiffened linen were in circa 1300-1350.
"Before the hour when the invention of printing permits cheap diffusion of works intended for propagation of ideas and for instruction of the masses, the possibility of multiplying pictures by a cheaper method of reproduction--engraving--had already been conceived. The idea of making books and ornamenting them with pictures came later.
But the privileges of gilds of "historiators" and miniaturists had to be reckoned with . They united to defend their rights against these new processes threatening harm to them. Substitution of paper for parchment, of printing with movable types for calligraphy, use of engraving on wood or metal, these all constituted a new danger for the gilds. Combination of these elements permitted production of illustrated books at a cheaper price than manuscripts.
At the beginning of the conflict the illuminators preserved the craft of coloring their pictures, which threw the engravers into a secondary place. The first printed books imitated manuscripts, because they were printed on vellum, in types suggesting the letters of the manuscripts, ornamented with miniatures or with engravings entirely colored by hand. They tried to give the illusion of being manuscripts. The first printers seemed not to want to harm illuminators trade."
Maybe with your more presise Historian enquiry you could write to the Vatican Library yourself. Your question was 'when start woodcut printing?' I presumed that you meant card's(not necessarily Tarot cards) and I thought Holy pictures were cards.~Rosanne