The University of Durham holds the family's Stainer originals.
See the Wikipedia Article and
the Encyclopedia Brittanica Article for his life. 
In addition, Hyperion Records has a write up, as does Choraline.
John Stainer, a Life in Music, by Jeremy Dibble, Boydell Press, Woodbridge, 2007.
John Stainer and the the musical life of Victorian Britain, by Peter Charlton, David and Charles, Newton Abbott, 1984.
Surge On! Stainer Centenary Snapshot, David Pennant ed, Pennant Publishing, 2001, contained family history. Its contents are on this website as articles.
Some Newspaper Cuttings found in a scrap book by Sir John:-
Cuttings A . . . Music Mistress's Starvation Wage, 'Grand Old Man' of Music, Note on a performance of the Crudifixion.
Cuttings B . . . Miss Stainer Organist Golden Jubilee, Article on Singing Birds.
Cuttings C . . . The New Professor of Music, The Executioner, A Crucifixion Ticket, Feat of Memory.
Cuttings D . . . Work and Play Cartoon, Articvle on Dancing, Jubilee Meal.
Cuttings E . . . Sir John Obituary
Cuttings F . . . Lady Stainer Funeral Notice
