Bill Leader recorded many albums for the Topic label. Musical Traditions introductory page describes how to search their extensive database:- http://www.mustrad.org.uk/discos/discog.htm
Such a rich career ought certainly to be documented and celebrated. I have been buying Bill's output since first finding the Folk Trailer sampler album so many years ago. It is almost incredible that such a body of work could be accomplished by one person. I look forward to seeing Guest Litto's book.