County folk magazines - efn, Unicorn, Folk London, Folk Write etc.
Flyers (mostly at CSH), for ceilidhs Webfeet.

Internet listings don't seem to work very well as many organisers don't provide listings as and when they are available - they have to have their arms twisted (very hard sometimes) for a press date.

(In checking half a dozen club web sites today, two had out of date listings.)

Time Out can make or break a gig in London.

Be careful about publicising events where you aren't the promoter. If a club is members only then they aren't allowed to advertise for customers "off the street". Islington only just avoided being closed down once because an artist sent our his own press release.