Face-to-face query (pitching)

If I see an agent at a conference, how should I approach them so I don't appear to be just one of the herd?
Approach them anyplace you happen to see them. Agents attend conferences to find new talent and projects to sell. They do want to talk with you. However, be reasonable. Following them into the bathroom is a bad idea. A much better one is to offer to find them in the bar or the restaurant, or the refreshment table and offer to buy them a coffee, or a drink, or lunch, or a new bowling ball . . . whatever is appropriate. Before you begin your quickie pitch, ask permission. "Do you have a moment to listen to a manuscript concept that may appeal to you?"

Cover letter. Query letter. Different purposes.

What is the difference between a cover letter and a query letter?
The query letter is a “sales document” intended to motivate the agent to ask for a manuscript submission. Some agents skip right over the query letter, and, as a first step, request writers to submit part of their manuscript with a cover letter. Its purpose is to inspire the agent to want to read whatever you have submitted. How to do this? Just like in the query letter, write a sizzling first paragraph that tells the plot of your story. Include the name of your protagonist, their goal, the obstacle (s) standing in the way, and a strong “tease” ending to motivate the agent to eagerly begin reading your accompanying manuscript. Keep your second paragraph brief and give the title, word count, and genre if it’s not obvious. Be sure to thank the agent for their time and consideration.

Picture book query/cover letter

For a picture book cover/query letter, do I begin with the story?

Yes. Jump right into two or three sentences and show your story as it pertains to the protagonist and their challenge (s). You can write a second paragraph to expand the story a little more, or place it all in one paragraph using five to seven sentences. Keep it brief. Give your background, writing associations you below to, hopefully one is the SCBWI (Society of Childrens' Book Writers and Illustrators). You don’t have to tell your entire story, that’s not the point. The purpose of this query/cover letter is to motivate the agent to read the attached manuscript.

Queries are about “showing” not “telling”

Many writers, when they begin the process of crafting queries, tend to tell "about" their stories instead of telling their story as experienced through the actions and emotions of the protagonist.
Telling about a story.
My story is about a little girl who enjoys visiting and snacking with her grandmother.
Showing the story:
Little Red, skipping through the forest heading toward her beloved Granny's cottage, sings a happy song in anticipation of noshing on their favorite food--hot, cheesy, garlicky pepperoni pizza.
The difference:
The first example lacks emotion or action and doesn't show the writer's ability to write a story. Reads like a newspaper article. Just the facts.
The second paints a picture, a personality, a mood, and involves the reader who immediately reacts by ordering a pizza.

Query overwhelm: welcome to “agentworld”

The most important part of the query is?

The first paragraph. Always. Why? Because most query letters are not read top to bottom. Sad, but true. Agents, buried under mounds of submissions, will give your query only a quick look to determine if the first paragraph grabs and sustains their interest.
This is why you must write and re-write those three sentences so they tell the plot and give compelling information about your protagonist and their challenge.
SENTENCE ONE: Introduce your protagonist (main character) and what they want in the first sentence.
SENTENCE TWO: Describe the obstacle (s) that stand in their way.
SENTENCE THREE: Hint at the possible outcome and the terrible "or else" that could happen if your protagonist does not succeed. Write this "tease" to motivate the agent to read your query second paragraph which expands the plot as it involves your protagonist.
Learn more about how to craft a compelling first paragraph by reading those posted on the "Evaluated First Paragraphs" page at The Query Club. http://queryclub.weebly.com/
As you’re reading these, think about what you would do to make them more effective.

Self-publishing vs traditional publishing

Self publishing, which includes paperless electronic publishing, is a route being taken by thousands of writers, many of whom have become frustrated trying to find an agent or a publisher.
Here's the challenge:
With self-publishing, you pay a company to edit, layout, create a cover, and print a certain quantity of your book. (Hopefully you have a dining room or guest room available for storage).
When it comes to marketing, you are totally on your own. And yes, you can create a website, offer your book through Amazon, then hit the road and promote your book with lectures, book signings, attending book fairs, searching out book reviewers, mentioning your title on book blogs, even locating an e-book distributor (along with Amazon) who promotes books and takes a % of sales. You'll find lots of information in the many "how to self-publish and self-market" books.
Self-published books are not, at present, sold by the major book store chains. Why? Because most simply don't measure up to the standards of content, editing, and design that book stores demand. They don't sell.
Becoming your own sales force brings up a major life question: do you want to stop writing to focus on selling?
Certain circumstances are perfect for self-publishing; writers who want to have their manuscripts published as part of their family history or writers who craft "nitch" books and know exactly how to reach their market. For example, I know a couple who developed travel techniques specifically for "pop-op" trailers. They sell books at travel shows, work with manufacturers of these trailers, and run ads in magazines catering to the "pop-up" camping market.
To educate yourself more fully about self-publishing, check out the programs at Lulu.com and Amazon's Createspace.com.