Publisher's Marketing Association
While www.grubstreetprinting.com is a great resource for small and medium size publishers, the Publisher’s Marketing Association (PMA) is the community where these same publishers learn and teach, recommend and kvetch, as each learns and shares publishing insights and methods.
PMA has grown to be assist much more than marketing. Check out their site and consider a membership. Their newsletters alone are worth the cost.
After reeling from all the advertisements for publishing services, you may even conclude you can handle your book production entirely on your own.
But since www.grubstreetprinting.com is a free service designed to save you money and introduce you to appropriate, responsible suppliers, why would you try the “trial and error” method of book production?