Below is a small sample of open access non-textbook books in communication and media. Others may be found by searching Directory of Open Access Books or Oapen.
Write Like a PR Pro: Why writing is still crucial in a digital and visual world (E-book) by 
Exploring Intercultural Communication 2.0 (E-book) by 
Writing for Strategic Communication (E-book) by 
Speak Out, Call In: Public Speaking as Advocacy (E-book) by 
The Hyperlinked Society: Questioning Connections in the Digital Age (E-book) by 