If you are interested in attending the Durham event, you can click on the sourcelink to RSVP. The event will take place on the American Tobacco Campus, Bay 7, from 10am to 6pm. And there will be "local snacks and beverages" on hand.
Google hasn't announced the rest of the tour yet, but if you can't make the event in Durham, perhaps there will be one closer to you.
source: +GoogleGlass via AndroidCentral