It would appear from the Doubletree reservations website that Westercon 65's hotel room block is sold out. If anyone else knows a way to get a reasonable rate, I'm interested. But if I'm forced to buy at the currently quoted rates ($229/night) I won't be going.
What the hell is wrong with Westercon that they wouldn't get options on a larger room block? It's one thing to sell out a hotel. It's completely bad planning to run out of rooms without having sold out the hotel.
EtA: this problem appears to be solved, and I've gotten my reservation now.