Simply so, what is the role of a publisher in music?
A music publisher's role is to make deals with songwriters, promote the songs their songwriters compose to musicians and anyone else who may need a song for advertising, a movie, a promotional campaign, etc., issue licenses for the use of the songs they represent, and collect licensing fees.
Similarly, why do I need a publisher for my book? The publisher essentially buys the right to publish your book and pays you royalties from the sales. If you want to publish a book traditionally, most writers need to find an agent. In order to find one, you must identify the right category for your writing.
Additionally, does the publisher of a book matter?
For books, publishers' brands matter in a direct manner to a greater or lesser degree depending on the circumstances. So, for example, the brand of Random House is thought not to matter at all to a consumer.
How does a book deal with a publisher?
Go to writers conferences where agents appear, search their websites, find their names in the acknowledgment pages of books you like, find a friend who has a good agent, and subscribe to Publisher's Marketplace for the latest book deals between agents and editors.
