If the book is too much like the one you have and was published in the last two years, the publisher may not be interested in another book like that so soon after the first one. Ideally, look for a publisher who publishes books in your niche but lacks a book on your particular subject. Make notes about the book and publisher, read up on the company in LMP and Writers Market for a better picture. Always check the Acknowledgments page in good prospects, as authors almost invariably thank their editors and agents. It's a good idea to call the publisher to find out if that editor is still at that house, as people move around often in the publishing business.
Publishers generally spend very little on promotion.
The promotion money usually goes to someone who has had a successful, if not fantastic, book. New authors should count on doing the promotion themselves, while discussing the broad outline of promotion with the publisher's PR people to avoid duplicating efforts. If the publisher sees you are doing a good job, they may kick in some promotion money, especiallly if the book begins to sell in bookstores or your efforts register sales with the publisher. Smaller publishers will make money with fewer sold copies than that. When sales slow, the author should consider contacting the publisher and offering to buy at discount the remaining stock for resale themselves.