UPDATE:
I talked to the guy in charge of the venue and he remembered WestFest III quite well. I hope that's a good thing.

They are quite booked and it only gets worse as the weather gets cooler and cooler. October and November are very busy out here. So...
The date that has been made available, with WestFest IV being penciled in, is
Saturday, September 30th. Don't go booking flights or making solid plans yet. I'm going to talk to the guy again in a day or two and make sure that we're in. There is a possibility that a later date in October might be available. He will be pulling the file from the last event to look over the details and then he will be confirming with the owner of the place that our previous deal is still good. I might have mentioned this but last time they waived a $6000 site fee.

When you see the site, you'll understand why they can charge that much. Keep your fingers crossed.
I will update you all again when this date is confirmed or another is selected. Thank you for your patience. Once the venue is secured, everything else will fall into place. I'll put up a website with all the details and hopefully will be able to line up some hotel deals as well.
Stay tuned!