Hi there Nick - long thyme, no sea!!!
Not clued up on Leeds, but try the Tykes News FILOFOLK website. There are a few things listed, although most of the music listed seems to be different nights at the Grove.
The musicians belonging to Les Panards Dansant - a group doing French dances mainly for fun have their own practice session which you might find interesting.
You must get in touch with us and organise a night out some time.
Quack!
Geoff!