Finding the perfect agent is like a fairy tale. When it all comes together it's a beautiful, magical, mythical thing.
1. Take Your Time.
I read somewhere that publishing's motto should be "hurry up and wait". That's true of a lot of parts of publishing, but there are lots of times we can make it better. Look at Snow White. From the minute we meet her, she's waiting for her Prince to come. But she's not just sitting there. Even when she runs away, she occupies her days taking care of the dwarves.
At no point does she stop everything to go look for her prince.
Writing a novel, and editing it, and having it critiqued, and editing it again... it's a long process. Yet people find themselves waiting until after they've constructed their query to look up agents. They you race through the process because it's holding you up.
No matter what stage of the writing process you're at, start your search now and you give it the chance to be organic. You don't have to stop everything to go look for an agent. You can come across agents and make a note of matches instead of spending hours combing books, forums, and websites.
2. Search, search, search.
Of course there is the possibility that the names of 5 to 10 perfect agents won't just fall into your lap, no matter how much time you give it.
Time to go Aladdin- a la Walt Disney. Princess Jasmine has to be married, and to a Prince. The Sultan uses all his resources and leaves no stone unturned in the search for the perfect suitor.
There are lots of places to find agent names and genres.
There's the Publisher's Marketplace listings, which you can browse for free.
Or you can find agent lists on forums like Absolute Write or Writer's Digest community.
There are also genre-specific communities that can help you find agents. In the YA world, there's YALITCHAT- which, like Publisher's Marketplace, has a free level and a paid level.
SCBWI, once again in the children's community, also has discussion on agents, but in the members-only area.
Check out the (insert year) (insert field) market series.
I haven't really looked at any of the other series out there, but I find it hard to imagine anyone else could be more comprehensive. They range from general writing to novel/short story to children's to songwriting. They're also available from Book Depository- which means free shipping for us not in the U.S. Except Pakistan. Condolences :(
If you're looking to publish in the UK market, you may want to have a book tailor-made for you. The Writers' & Artists' Yearbook is just what the doctor ordered. I own a copy of the Children Writer's edition. It has wonderful lists of agents, and informative articles from the big fish of British publishing- Roald Dahl and J.K. Rowling, to name a couple. I recommend that if you're looking at the UK market you definitely pick up a yearbook. The UK market isn't as online as the US market. And there are entire agencies thta you just won't find online.
(Insert year) Guide to Literary Agents is just what the name says. It offers advice, explanations and listings of both American and foreign agents.
I'm a people person. I'd probably do a better job of talking myself into a 3-book deal than writing/querying myself into one. Conferences, workshops, regional writing group meet-ups are great places to meet agents. And having a chance to interact with them and ask questions can make it feel less like they're are some holier-than-thou ruler-of-the-universe and more like a business partner.
3. If the shoe fits.
It's tempting to think that because an agent reps your genre, they're a match for you. That is not necessarily the case. Lord of the Rings and Harry Potter are both fantasy, but they're wildly different.
Of course, Cinderella will help us with this one. Prince Charming had her shoe, and knew that when it fit, that was the lady he was looking for. Did other people get their foot in the shoe? Yes. In almost every variation of the tale, someone manages to squish their hoof in there. But it's never a good fit. Realisitically speaking, there'd probably be more than one woman in a whole kingdom who could fit the shoe. But that doesn't mean Prince Charming should marry anybody in possession of a foot.
A while back the venerable Nathan Bransford spoke about spaghetti agents- agents who sign anything with a modicum of potential and then throw all the MSs at editors and see what sticks.
I don't want to be a spaghetti querier- querying every single agent who reps my genre, in the hope that one sticks.
So how do you find the girl from the ball?
This is where time comes in. Anytime you come across a book in your genre that makes your skin crawl, make a note of the agent. An agent usually only works with what they LOVE! So if they loved it, and it makes you want to gouge your eyes out, then you maybe have different tastes.
On the flip, if you absolutely LOVE LOVE LOVED a book, make a note of that agent too.
Making an agent list ahead of time gives you the opportunity to check out books that an agent has repped if you hadn't previously read any of them.
Also, lurk around the bloggosphere. You'll pick up little tidbits from agented writers about their agents style. Of course, they'll be more professional than to air their qualms on the internet, but you can find out whether an agent is editorial or not, what their process is like, and whether they'll call to wish your dog happy birthday.
I'm not saying you need an agent who remembers your dog's birthday. But if that's what floats your boat, the best way to find out is from their clients.
4. Is it the real thing?
In Studio Ghibli's Princess Mononoke, the humans disguise themselves in the skins of the dead boars in order to attack. When you mistake foe for friend, the effect can be devastating.
Real agents want you to succeed. Your success pays their mortgage. But there are oodles of fake agents out there who just want your money and care nothing about your success.
Always check it out if an agent asks you for money. I do know of a few agents - all the ones I can think of offhand are UK-based- who offer paid critiques completely seperate of their agenting business.
Check the Association of Authors' Representatives. As far as I know this is completely foolproof, BUT they require an agent to have been agenting for 18 months. New agents fall by the wayside. (Being included in any of the resources in the search section is also a validation.)
Look for connections to a reputable agency. If other agents in the same agency have AAR certification, the agency and therefore all it's agents are legit. There are certain big name agencies that have been around forever and also pretty much guarantee legitimacy: Curtis Brown (US/UK) and Conville and Walsh (UK) for example.
Affiliations with reputable conferences. If they've given a workshop at The Festival of York (UK) or SCBWI Summer Conference (LA), then you know they're legit. The same goes for being members of the large writing/publishing associations: SCBWI, RWA, etc.
Poke around author websites. If J.K. Rowling says on her website that person is her agent, then they're legit.
If you haven't encountered them in anywhere you'd stake your MS on, check them out on Preditors and Editors.
Good luck finding your happily ever after!