Ten Tips on Contacting Literary Agents
1) Carefully study the literary marketplace before querying agents. Buy Jeff Herman's book Writer's Guide to Book Editors, Publishers, and Literary Agents; select about six agents who represent authors of books similar to yours. (Don't ever select an agent who charges money up front.)
2) Go to each agent's website and read the guidelines for contacting him/her. If she says "query only," send just a query. If she says, "send a query and brief synopsis," that's what you should send. Give the agent only what he/she asks for. (It annoys them when they get more!)
3) Make sure to send a self-addressed, stamped envelope (SASE) with your query so the agent can respond to you. If you don't, you won't hear back.
4) If an agent says it takes three months to respond to a query, wait three months before following up. Follow up with a brief note or an e-mail. Don't ever call an agent.
5) If an agent asks for three sample chapters, send only three. Make sure to send an SASE that is big enough and with enough postage to get the chapters back to you. If you don't, you won't likely hear from that agent again.
6) If an agent asks for your whole manuscript, send it with a self-addressed, stamped mailer or box so it can be returned to you. Many office supply stores have double-box sets designed specifically for authors.
Note: I can't stress SASEs and SASBs (self-addressed, stamped boxes) enough. I edit about 35 books a year, and only about 5 of those manuscripts are mailed to me with a mailer and enough postage to get it back to the author. I go out, buy a box, pack it, take it to the post office, and buy postage. Then I bill the author. Agents will not go to this trouble. They won't even read your manuscript if there's no return SASB with it!
7) From time to time, one of the writers' magazines lists agents who're accepting manuscripts. If you see one of these listings, wait at least three months to query those agents; they will be inundated when the listing or article first comes out.
8) I have a good article on writing query letters (fiction and nonfiction). If you would like a copy, please send me an SASE (regular, business-size), and I will mail it to you.
9) I don't write queries and synopses for authors, but I do critique and line edit them. (If you're interested in receiving my rate sheet, please request it by sending me an e-mail at firstname.lastname@example.org.)
10) If an agent asks for your manuscript, send it as soon as possible. Make sure it's in standard manuscript format. (See guidelines on this website under Articles.) Print the manuscript on good quality white paper.