So pay $50 for a book that will save you two dozen hours of research, and then spend a dozen of those hours writing blog posts and tweets telling other people exactly which easy steps they can take to promote open journals and so on. That accomplishes your goals a lot better than not paying for the book.

Or, if you don't happen to predict that evangelism is the optimal strategy in the context then you can use the dozen hours writing up blog posts or papers that directly convey knowledge freely.