I broke down and purchased a subscription to Publisher's Marketplace. It's 20 bucks a month, which is pretty expensive when you consider the accumulated annual price. However, I've already sent a query package (which included a partial--love it when they let you send partials with the query) to an agent I hadn't seen on any of the public boards. And today I'm going looking for more. Some of them look like absolute noobs -- or scammers. One guy only has a yahoo account listed as his contact method. Another was broadly discussed and ultimately dismissed as a scammer at Absolute Write. But there are some gems in there.
Now that everyone is NaNo-ing (well, not everyone; you guys all seem to be skipping it), I'm hoping the agents have a noticeable drop in queries, thus having time to give some attention to mine.