You can just Google the names, but anyway here are some website links for whatever soundclips they offer:

Coope, Boyes & Simpson
Dave Webber & Anni Fentiman
Graham Metcalfe, Ian Giles and Ian Woods (no website) normally perform individually (Ian Woods has also written a number of widely sung songs), but they have recently also teamed up to form "GMW" for a number of gigs. Baritone, tenor and bass in their ranges respectively, they have a wealth of mostly traditional material.