If you like Ravilious' work and can find a copy, "An English Eye" (ISBN1855226286) is well worth getting. 113 beautifully reproduced photographs and an insightful commentary by Peter Hamilton which includes an account of James' working methods. "Down the Deep Lanes" is currently available from amazon.co.uk and while billed as a paperback, mine arrived as a hard cover. In this case there is nothing in the text about James' methods and philosophy however.