Made it to Airgas and replaced CO2 bottle, although I was 15 minutes late. Luckily they were still open. (Note to self: Airgas closes at 4:30. Leave work earlier and don't depend on somebody else having a late rush order to keep the Airgas guy there after closing time.)
I got some "Maximum Bubble" or some such from the toy section at Walmart and started tracing the leak. As I suspected, there were leaks at the joints in my homemade manifold. Since we all know from basic reliability centered maintenance theory that overall reliability decreases with the number of parts in the system, I got rid of the extra pieces and reassembled everything. Max Bubble says the seals are tight so maybe I'll have some gas in the morning.
090602 Geordie Ale: Kegged
I racked the brown ale to keg after I eliminated the CO2 leak. I didn't start carbonating. I'm going to try the rapid force-carb technique that HBT member Yuri_Rage recommends in this post. I need to get the beer down to 40 F first, so it will sit in the keg overnight chilling, and tomorrow after work I'll give it Yuri's shake-rattle-and-roll approach.
O for a ring
I ordered some new keg o-rings from McMaster-Carr on Sunday evening and they were delivered today. Great service!