Quick Answers: Age Groups, Beginning Illustrators, Librarians

I'm about to start querying my novel (workshopped, re-written, etc.) to agents and feel I've put together a pretty good query. But, I stumble over how to define the novel. It's a 55K word urban fantasy with twins that turn 13 in the first chapter. It seems to me that the characters maturity (or lack thereof) plus a few nonsensical elements place it as a mid-grade, but I wonder if the age of the characters make it YA. Is there a sharp line delineating the catagories? Or, perhaps more likely, are there widely accepted defining points that apply to this situation? Should I send out x number of queries calling it a MG, and y number calling it YA and see which fare better?

There isn't a distinct border between the age groups-- or, that is to say, some people's distinct border is different from other people's distinct border, like neighbors who are always arguing about the property line. Take your best guess, and stop worrying about it--if we like what we read, we'll forgive it easily if you think it's MG and we think it's YA. That's a slight tweak in the terminology-- no big deal.

What we don't forgive as easily is if a person thinks their "fictional novel" is for preschoolers or something like that-- some designation that's so far off base that we have to worry about their relationship with reality, and what that will mean for the publishing process. People with low reality IQs are a huge pain in the ass.

I am a childrens book illustrator, however have not yet published my first book. To be completely honest - I don't quite know where to start.
So far my research has shown the first step (after completing your work of course) is sending out query letters. How should an Illustrators query letter look?
If you could offer any advice on how to get started, it would be really be a great help...I just know I have some wonderful illustrations to offer the world!

If what you're trying to sell is a book, then regardless of whether it's text and illustration or a wordless book, your query letter should look the same as any other author's.
If you're trying to get illustration work with samples from your portfolio, then you should be looking up publisher's art submission guidelines and following those. Possibly you can participate in a portfolio review, and you should definitely have a portfolio up online.

Between 1995 and 2000, I wrote four nonfiction series books for two different publishers. Both publishers seemed happy with my work and asked me to do more. However, just at that time, I started moving up in the ranks of my actual full-time paying job in a library. I made the decision to concentrate on my career and my family, with spare time devoted to reading, rather than writing. The writing I have done during the intervening ten years has been professional in nature: book reviews, journal articles, a book chapter, and a book.
Now I am ready to go back to writing children’s nonfiction. I have several projects I am researching for possible books.
My question: how much do I have to explain my hiatus in publishing when I query editors and agents? If I just say I wrote these four books in the late 90s, will they wonder what’s been going on? I don’t want to over-explain, but I also want them to know that the break was my decision, and not because I couldn’t get anything published.

Do explain very briefly that you've been concentrating on being a librarian in the meanwhile. Not only does that give a reason for your past titles being long out of date (and thus less useful to us as comparisons), it also tells us you're a librarian! We like librarians.