Cover designers
You have a finished manuscript and a retailer's grid to survive. A book cover designer decides whether a reader stops on your title or scrolls past it, and the work is not decoration: it is the jacket that has to carry genre, tone and author name at a size no bigger than a postage stamp. People arrive here with a custom book cover in mind, or with a series that needs one look across several volumes.
The tags split the category by where the designer sits, and that changes what you get. United States listings tend to work with the big New York houses and with self-published genre fiction, so they know how a cover has to read at thumbnail size on a retailer's grid. United Kingdom designers often come out of traditional trade publishing, which shows in typography and in restraint. Australia and Canada each hold a smaller pool, and choosing there means shorter distances, same time zone, and a designer who knows the local market's bookshops.
Within any of the four, the listings divide again by what they actually make. Some, like Bookfly Design or Elderlemon Design, build covers for fiction and series work, where a look has to hold across several books. Others, such as 1106 Design or Brisbane Self Publishing Service, take a manuscript through layout and print files as well as the front. A few, David Airey among them, come from branding and identity work, which suits nonfiction that needs to look like a business rather than a novel. Pick the branch that matches your book before you pick the name.