Since Mary Ann started it, I'll add my two cents on the dreaded act of querying.
On Fridays I set myself a goal of querying five agents for the YA project I recently finished. (Well, abandoned is the proper term. Leonardo da Vinci has been quoted as saying, "Art is never finished, only abandoned." And writing is art, right?)
On the Fridays when I actually succeed in getting five whole queries out, it's my project for the whole day. I don my anti-sensitivity-to-rejection armor, as writer friend and fellow Guppy Donna Glaser/Gracie Daniels recently called it, and pound them queries out. I have a long list of agents I've gathered over months and, let's face it, years. But I still have to check each one to see if he or she is still at the same agency, or even still agenting. I've also gathered some research sites that I'd like to share with anyone in the query-go-round game.
I joined querytracker.net, an excellent place to keep track of the queries and also to research. QueryTracker brings up agents by genre, by whether they accept email or snail mail queries, and other criteria. Other user leave helpful notes and there are stats on reply times, percentage of requests for further material, etc. I like this site so much I joined as a Premium member, which gives me a few more bells and whistles, but it gives you a lot for free, too.
When seriously querying, it might be worthwhile to pay to join http://publishersmarketplace.com/.
A free month is offered occasionally and you can get a lot of research done in a month. Another ploy for using this site is to google publishersmarketplace and the agent's name. This will tell you how many recent deals the agent has made, although you can't see them without joining.
The water cooler at http://www.absolutewrite.com/forums/ can yield results. You have to register to post, but anyone can read comments on particular agents. This site can be searched: http://www.guidetoliteraryagents.com/blog/. This site,
http://www.agentresearch.com/, charges for searches, but I don't know anyone who has found them extremely helpful. There is also a free service available. It's a good idea to check an agent at http://www.anotherealm.com/prededitors/ to see if there are negatives posted. If you're open to a British agent, try http://www.writersmarket.co.uk/.
And, of course, google and yahoo searches should be done. I've found interviews doing this which give me some insight into how to write the kiss-up line, I mean add the personal touch in the query letter.
The thing you need most when querying, after the thick skin for the rejections, is PERSISTENCE.
PS. One I left off: agentquery.com. Great site!
(Next week I'll post my Magic Number Theory.)