I’ve just read this article by Michael Nye, the editor of The Missouri Review, about writing cover letters to literary magazines. While we here at the Sequoya Review don’t read cover letters (since we are such a small staff and know all of you anyway, we do it blind), if you want to submit to almost any other magazine a cover letter is nigh-required.
Nye’s best advice is this: “Short and sweet is really the way to go here.” I tend to agree, whether you’re talking about your past publications, figuring out a subject line, mentioning a previous meeting with the staff, or whatever. Don’t talk about the submission—it’ll speak for itself, good or bad. It’s really pretty simple but apparently a lot of people overthink it, so don’t sweat! If your writing is good, it’ll get published. Simple as that.
Sequoya Review 
Always good advice, Case!
Robert, they vary. It’s up on the authors. Numerous in the letters arising are handwritten, or hand-notated, it is really about fifty percent and half. While almost all of the 1st letters were typed. The fourth letter was a comic.