Don't want to steal Dick's thunder or rob him of any possible revenue from the sale of his tutor, but Roger Watson produced a very nice, simple concertina book some years ago. It's called 'Handbook for English Concertina' and was published by Wise Publications (London, Sydney, New York)and was distributed by Music Sales Limited, 78 Newman St. London W1P 3LA. Don't know if it's still available, but perhaps a 'net' search for the distributor, or Roger Watson himself will bear fruit.

Regards

Andy