Since others raised the issue I thought, for the sake of completeness to answer the question regarding Sheffield's folk activities. The following are all considered by their participants to be Sheffield based.

Clubs: Royal Traditions, Sheffield Storytellers, 1st & 3rd Acoustic Club,Booit Straps FC, Hillsborough Folk, The Story Forge, Rivelin Folk, Sheffield Ballads Club, Raise the Roof, Crookes FC, Beehive FC, Cartwheel 3, No Smoke Foke, Play On, First Friday, Royal Folk, Wortley FC, Robber's Dog FC.

Dance teams etc: Sheffield Uni Ceilidh Soc, Pecsaetan Morris, Sheffield City Morris, Three Rivers Morris, Boggart's Breakfast, Sheffield Giants, Handsworth Sword Dancers, Grenoside Sword Dancers, Sharp's Ladies Sword, Triskele Sword.

Singers and Bands: Roy Bailey, Martin Simpson, Robin Garside, James Fagan & Nancy Kerr, Jon Boden, Fay Hield, Gavin Davenport, Richard & Jess Arrowsmith, Helena Reynolds, John & Vic Bowden, James Reynard, Simon Heywood, Raymond Geeenoaken, Kate Green, Sheffield Folk Chorale, Graham & Eileen Pratt, Gloristrokes, Skyhook, Hekety, Tinculo.

Sessions: Fagin's, Hillsborough Sessions, Kelham Sessions, Riverside Sessions.

Now it would be churlish perhaps to remark upon the proximity of Kate Rusby, Damien O'Kane, Dave Burland, Hedgehog Pie, Maltby Phoenix Sword, Barnsley Longsword, The Rock FC and many other folk entities so close to Sheffield as to easily be accessed and who are frequent participants in folk activies in the city.
Paul