I can't claim to be the authority on local festivals and parties, but I recently came across this really cool web site called "World-Party" at http://www.world-party.com. They seem to list hundreds of year-round events all over the world, like music festivals, full-moon parties, pagan gatherings :) etc. Check it out - I hope you find what you need.
For something really unique, try the Crab Apple Fair at Egremont. It is during this festival that the world gurning (face pulling) championships are held. For more information, and to see an online version of the competition(!), be sure to check out http://www.cumbria.uk.com
Go to the Puck Fair in the west of Ireland (Co. Galway, I think). They find a goat, name it "Puck" and dedicate a week-long festival to this goat. There is lots of traditional Irish stuff (including music, dancing, races, drinking), and this one's a bit off the beaten track (at the moment). If it's festivals you're after, Ireland's the place to go in summer - there's always something on somewhere in the country - any excuse for a shindig!
