This comes from the Gregorian Institute of Canada, at McMaster University, and includes a vast amount of material from this old English rite. Here’s their summary of the project:
The Sarum Rite of the Western Church developed through the period 1066-1558, and was used throughout much of Great Britain and parts of North-Western Europe. Sources for the Sarum Rite rite exist in a considerable number of medieval manuscripts as well as a large number of printed editions dating from the late 15th and early 16th centuries. Under the rule of Elizabeth I, the Latin Sarum Rite was finally abolished and replaced (in Britain) by the English Book of Common Prayer. The Gregorian Institute of Canada is in the process of publishing The Sarum Rite, containing the full text and music for the Breviary Office, for the Processional, and for the Missal. This edition is being published serially in PDF format. Publication began in January 2006. New installments are published every six months.
Since 2010 The Sarum Rite is also being published in an English edition. The English Performing Edition conforms to the text-style of the Book of Common Prayer and the King James Bible. This Performing Edition facilitates performance by streamlining the rubrics and by reorganizing the material where appropriate. The English Scholarly Edition (in progress) will conform to the text-style of the Challoner-Douay-Rheims Bible, which follows the Vulgate, and will follow the same order as the Latin edition.This project aims to be both historical as well as practical. Its connection with the living traditions of the Church can be to a great extent understood through the prespectives presented by László Dobszay in his recent book, The Restoration and Organic Development of the Roman Rite, London: T & T Clark, 2010.