As for previous COSITs, the proceedings for COSIT 2009 will be published by Springer in the LNCS (Lecture Notes in Computer Science) series.
Information for authors of LNCS articles can be accessed directly from Springer at http://www.springer.de/comp/lncs/authors.html. Information on previous COSIT proceedings published in LNCS can be found in the Proceedings section of the COSIT series website.