How can I find out which publishers are most likely to be interested in a new novelist?

Beginning Writer's Answer Book edited by Jane Friedman

There are several ways. You can research publisher listings through a market
guide and look at the percentage of new writers they publish; you can read magazines like Booklist, Writer’s Digest, and Publishers Weekly, which periodically give profiles of first novelists and information about their books; or you can browse through the fiction shelves at the bookstore or library and look at author bios, then note the publishers of first-time novelists. One company particularly known for its support of new novelists is MacAdam/Cage, an independent book publisher based in San Francisco. They still read unagented manuscripts.