This month I'm teaching an on-line course for MWA Mystery Writers of America www.mysterywriters.org entitled How to Write a Kick-Butt Query Letter! The resources we're using (See below) are thorough in the nuts & bolts of query letter construction, i.e. One single-spaced page of 250-300 words condensed into 3 to 4 paragraphs, a double space between paragraphs, each paragraph with a designated purpose, title and word count mentioned in first paragraph (80,000 to 100,000 wds. for adult, 40,000 to 60,000 for young adult), all typed in Times New Roman 12-pt. font size.
I used these same guidelines in my award-winning first novel Deadly Choices. http://www.jenniespallone.com/ Yet life is not just in the structure of a query letter, but in its overall "personality." The gusto that inspires a literary agent to ask for the first three chapters of your manuscript rather than toss your letter into the land-fill. Tune in for more on this subject....
Writing a Successful Query Letter, Joe Moore, KILL ZONE blog, 3/11/2009
How to Write a Query, AGENT QUERY
Query Shark Blog, Janet Reid
How to Write a Query Letter for a Mystery Novel, Nancy Curteman blog, 11/4/2010