Before you can set RDF links manually, you need to know something about the datasets you want to link to. In order to get an overview of different datasets that can be used as linking targets please refer to the Linking Open Data Dataset list . Once you have identified particular datasets as suitable linking targets, you can manually search in these for the URI references you want to link to. If a data source doesn't provide a search interface, for instance a SPARQL endpoint or a HTML Web form, you can use Linked Data browsers like Tabulator or Disco to explore the dataset and find the right URIs.
This brings us to the first big “con:” you’ll have to do all the work—and front all the money—yourself. Advertising is not cheap. Getting your book reviewed by major industry reviewers is not cheap. Buying advance review copies of your own paperback to distribute to reviewers and bookstores is not cheap—and getting bookstores (and podcasters, and media) to pay attention to a self-published book takes work. Being a self-publisher means taking full responsibility for your own book, from the cover you choose to the editor you hire, and that responsibility will cost both time and money.