Step one of any venture is always preparation. Hence, I get this:
Accept no substitutions. I actually have the 2011 edition already, but times change and you always want to have the most up-to-date info. The 2012 edition just out on the 6th, so that's pretty damn bleeding-edge. Finding it was annoying, in large part due to the rain LI got this past week. Barnes & Noble had ordered one copy, which was snapped up before I got there. The closest available copy was in the city, and no way I could go that far, so I just think "F it", and grab it off their online store.
For my trouble, I wind up getting home from the day job at 7, cranky from all that driving in the rain. And now I've got to wait three days for it to come in the mail. Totally the worst of both worlds.
But I've got it, and hopefully I have a somewhat better idea of how to use it than last time. During my initial agent search, I browsed through the whole 2011 edition, picking out about 40 or 50 agents that looked promising. I copied down names, agencies, and URLs, putting them in a spreadsheet. Then I ran what I had past Preditors and Editors, because a few scammers always slip by the screening process. After that, I started to overdo it. I looked them up on Publisher's Marketplace, and rated each of them on how many books they'd sold recently, how much money they brought in, and how in synch they were with my subject matter. That turned out to be a lot of wasted effort because, realistically, you're going to query them all anyway.
Querying is not like applying for college. I was treating it that way the first time, applying to inferior "safety schools" that I could fall back on if I got rejected from the big agents. However, an incompetent or dishonest agent is worse than no agent at all, because your book will sit with them and never get sold. And once you've weeded out the incompetents, prioritizing the remainder is pointless. You don't know what kind of offer you'll get from them until they present it to you, and you're a fool if you just assume you'll have more than one offer to consider. You won't. The market so glutted with manuscripts seeking representation that you're lucky if you can attract the attention of even one legitimate agent.
Fortunately, all you need is one good one. Getting her to notice you is the problem...