Every writer should have a professional library that includes books aimed at both the craft and business of writing. Here are a few of the resources you'd find on my shelves. (This list is tailored for U.S. writers, but I am sure there are equivalents in your countries.) You won't need every book or magazine on this list, but you'll definitely find at least some of them useful.

• A subscription to Writers' Digest Magazine - available in both online and print versions.
• A subscription to Poets & Writers Magazine - available in both online and print versions.
• A subscription to Publishers Weekly - available in both online and print versions.
• Publishers Lunch - I get the free version of this newsletters.
• Writer's Market 2018 - Kindle and Paperback versions available.
• Guide to Literary Agents 2018 - Kindle and Paperback versions available.
• Novel and Short Story Writer's Market 2018 - Kindle and Paperback versions available.
• Poet's Market 2018 - Kindle and Paperback versions available.
• Children's Writer's & Illustrators Market - Kindle and Paperback versions available.
• The Complete Handbook of Novel Writing - Kindle and Paperback versions available.
• Planning Your Novel - Kindle and Paperback versions available.
• Understanding Show, Don't Tell - Kindle and Paperback versions available.
• Fool Proof Outline - Kindle only.

Some of these will get you started. They won't all work for you, but they will get you started.