Most magazines are copyrighted, and their copyright doubly protects your personal copyright. Newspapers are seldom copyrighted, although syndicated columns are protected. Government publications are not copyrighted either. If you write a book, the publisher will register your copyright; but make sure he registers it in your name, not the name of the publishing house.
If you wish to copyright your material as a safeguard, send a copy of the material, a registration form, and $35 if filing electronically. See www.loc.gov/copyright for information and forms. Or send a paper copy to: Publications Section, LM-455, Copyright Office, Library of Congress, 101 Independence Avenue, SE, Washington, DC 20559. The charge is $50. The telephone number is 202-707-3000. The hotline number to request forms is 202-707-9100. For a general packet on copyright registration request #118. You can register as many of your articles, stories, and poems as you like under the same copyright, as long as all the material is sent to the Copyright Office at the same time.