I have translated a wonderful children picture book from Hebrew that addresses social and emotional intelligence and compassionate communication geared toward children ages 4-8. The book sold 100,000 copies in Israel since 1999 and now we are seeking a US publisher.When you say that the book addresses "social and emotional intelligence and compassionate communication geared toward children ages 4-8", I cannot be sure whether you see "very preachy" as a plus or a minus. If you see preachiness as a minus, be aware that your query letter may be giving the wrong impression.
I am wondering how to find a publisher or an agent for such a topic since the books that I see in the market are very preachy, written by therapists and published by big publishers that do not accept unsolicited manuscripts.
I know there is a huge market in the US for this book because the author came for a tour last December with a play based on the book and I was able to arrange many performance with almost no effort. People where begging me for books after and before the performances. I am just puzzled with how to break in the market.
Would appreciate your professional advice.
I should also mention that based on the mistakes in your question (where / many performance / children book / break in the market), your translation may be giving the wrong impression as well.
If you are talking about a book published by an Israeli publisher, then (as I've mentioned before) the answer is that usually publishers in other countries are pursuing contacts at the large publishers themselves in an effort to sell foreign rights. As a fellow publisher, the 'no unsolicited manuscripts' rule doesn't apply to them. If this is the situation we're talking about, I don't understand why you would be the one pursuing a US publisher. (And just in case: if you don't work at the foreign publisher, you can't contact US publishers and say you're "representing" the foreign publisher.)
If you are talking about a self-published book, however, or (regardless of the term you use) any "publisher" where the author takes on the burden of selling the book, then you are effectively in the same boat with any other author attempting to find an agent or publisher, and all the same rules and advice applies-- except that you must also inform everyone you query or submit to that Hebrew rights are not available.
I hope that helps. Good luck!