I love Count Basie on "For The First Time", and with Oscar Peterson on "Satch And Josh". These guys are hardly unknown, but these efforts are way undervalued in their catalogues. Similarly Duke Ellington's album "For Blanton". Check out Jessica Williams "Jessica's Blues" - I defy anyone to dislike this album. For some relatively unknown Kiwi artists try pianist Mike Nock (I love "Ondas" on ECM), and an "acquired taste" jazz singer called Malcolm MacNeill "Skylark".