Can you be more specific as to the nature of your book.? is it fiction or non fiction, creative writing or self help, academic or technical et cetera.
To the point, most reputable publishing houses will front you money for a good marketable manuscript. On the other side of the coin, if it is " vanity publishing " or a self published endeavor, then you may have to pay for your book to be published. The later is not really an advisable option to take, as you " may "end up paying lots of money for books that you may perhaps not be able to sell except to family, friends and neighbors.
You can google your question and you will find plenty of answers to your question. Check websites of publishers and read their conditions, criteria, requirements and inform yourself well in everything.
Remember that, most book publishers and distributors, will rarely touch a self published work, except in the area of music publishing where it does not really matter who publishes the work. Also remember that it is a lot of investment in terms of everything that makes it a tricky business for both publishers and authors. So having a publisher to pick up your work is a better choice, as they will put effort, money, time and every available resource to recoup their investment..
Also the electronic revolution in terms of digital delivery is changing everything fast, some authors are opting for this, as it may not really require all the traditional approaches to publishing. This option might offer would be authors many choices, but a relatively low returns in sales, reading audience, publicity et cetera.
In any case, if you would be more specific and provide a clue as to what you are looking for, perhaps it will be easier to provide more useful and helpful information.