You can find accurate e-mail addresses to send query letters to specific editors of Publishing Companies online from http://www.acqweb.org/email-ad.html. They provide Email Address Directory of publishers in an alphabetical order. It is a service that is provided under the Library Community.
Each company generally has it's own submission guidelines, it probably wouldn't be a good idea to ignore them. You can check their websites - there is usually a link that says "submissions" or "prospective authors".