OAPEN (Open Access Publishing in European Networks) has announced the Directory of Open Access Books (DOAB).
DOAB will provide a searchable index to peer-reviewed works published under an Open Access business model, and links to the full text. The beta version will be made public in spring 2012.
DOAB seeks to increase the discoverability of OA books. Publishers will provide metadata for the OA works, and the records can be used by aggregators and library catalogues.
The OAPEN Foundation is an international initiative dedicated to Open Access monograph publishing, based at the National Library in The Hague.
See the OAPEN press release.