The next one is on Sat 26th March, 2011. 12.30pm-3.30pm. Well worth a visit!
For those on Facebook, check the Write Note Grimsby Write Note Grimsby acoustic music group on Facebook
There is info re the general format and 'rules' of conduct etc.
Also check out Steve Jackson's Write Note in Lincoln as I think the two groups run on different weekends, deliberately, so that people can choose to attend both if they wish. I will try to find the link for that, too, unless some kind soul beats me to it!