Try out the Fremont Market:
http://exploitseattle.com/index.pl?node_id=1076
It is a weekly event and at the moment the entry will just place itself for the next month. Events which occur for just a set number of days, such as Stone Soup Theater's The Lion, the Witch and the Wardrobe, will just appear for the days that they occur on.
Still a few kinks to work out, like exact times for events occurring multiple times on one day, but its nice to get this much working :)
Next, pushing data into Google Calendar :)