How can I research the success publishers are having with sales of the books they market? Outside of purchasing Publishers Weekly, that is... My idea is to measure how well they perform their marketing. Thanks in advance.
Sales can be a tough thing to determine. But often publishers will put little blurbs in their catalogs (usually downloadable on their websites) next to book titles to encourage stores to order certain books. eg, "title x: over 50,000 copies sold." I think this is good b/c it points to what a publisher has done for a title. Not necessarily what your book will do, but it would be indicative of an active marketing department.
Publisher blogs can also be a good source of information on sales. They'll often announce when titles go to second printings, or when titles hit certain benchmarks: eg. "Bestseller" which, depending on where you are, can have different meanings, so be sure to qualify what the publisher is saying by "best seller." In Canada, for example, a "Canadian Best Seller" requires 5000 units sold. Not saying that's a huge number, just that you need to know how the term is being used.