Some sources to learn more about the Open Access movement in general:
Scholarly Publishing and Academic Resources Coalition (SPARC)'s page and resources on Open Access
Presents a snapshot of the global Open Access movement, focusing on the member states of the United Nations Educational, Scientific and Cultural Organization (UNESCO)
A wiki that collects topics common to Open Access publishing, and information about them
A 2010 bibliography of sources about various topics in Open Access
Videos about Open Access, from the Open Access Week website