Peter Suber is one of the leading authorities on Open Access. He is the Director of the Harvard Open Access Project, a senior researcher at SPARC (Scholarly Publishing and Academic Resources Coalition), and a Fellow at Harvard's Berkman Center and Office for Scholarly Communication.
Budapest Open Access Initiative:The Budapest Open Access Initiative is an international effort to promote Open Access publishing online.
Open Access Overview: A brief overview of open access from Peter Suber.
Open Access Week: A website with resources for celebrating Open Access week every October.