If you're into visiting Renaissance Fairs while traveling here's a pretty comprehensive list of them around the country along with pirate, fairy, and some Celtic themed events.
I am familiar with that list. Our schedules don't really let us make long trips these days, but we are lucky to have several within driving distance of DFW. Normally we just go to Scarborough Faire in Waxahacie, but the last 2-3 times we have gone the heat just about killed us by the end of the day.