The JS Bach Short Preludes and Fugues (not to be confused with the Short Preludes and Fugues BWV 553-560 which have full pedal parts) are an excellent introduction to the Inventions or the Wohltemperierte Klavier, and were composed by Bach for this very purpose. They make good short service voluntaries – some are quite easy, others less so. Mine is a Peters Edition (Nr 200a), and you’ll probably find them catalogued under piano music.
If you have already learned them on the piano, many of the movements of Bach and Handel’s suites transfer nicely to the organ -the Allemande from Suite No.4 BWV 815 for example.
Handel 7 Kleine Fugen fur Orgel oder Cembalo
I downloaded mine from Werner Icking Music Archive
Edited by the indefatigable Pierre Gouin/Les Editions Outremontaises.
All the early English keyboard repertoire is very useful: for example
Weelkes 2 Voluntaries and Tomkins Verse
From Early Organ Series Vol 2 Edited by James Dalton
Faber Early Organ Series (print to order)
I get a few raised eyebrows, but I am a fan of Henry Coleman! Look out for his books of Voluntaries for American Organ or Harmonium. Some are still in print, though I also found some on ebay. I particularly like the practical optional cuts/repeats in some of his pieces.
Elgar Vesper Voluntaries Op.14
No3 for example is playable manuals only, except for a pedal F for the last few bars.
Look at the Oxford Service Music for Organ series compiled by Anne Marsden Thomas. Books 1 and 2 Manuals only.
I can’t get excited about many of the pieces in the huge number of Kevin Mayhew books of new music written for manuals-only organists. However their Essential Organist for Manuals has been a life saver (particularly the very first piece in the book, which is a manuals-only transcription of Jerusalem). I have no problem in using easy transcriptions, while I find my feet – the congregation would rather hear an easy piece played well, than listen to someone struggling.
Another Kevin Mayhew I have found useful is Preludes & Verses, a collection for manuals, edited by Adrian Vernon Fish. Buxtehude, Bach, Couperin, Sweelinck, Reinhard – good stuff.
And another Kevin Mayhew – A French Collection for piano, organ or manuals. Eases you into the French repertoire, from Couperin and Charpentier to Boellman and Franck.
See also Manuals-only repertoire 2