WSMO Studio is an open source Semantic Web Service and Semantic Business Process modelling environment for the Web Service Modeling Ontology. WSMO Studio is available as a set of Eclipse plug-ins that can be further extended by 3rd parties.
WSMO Studio features include:
Front-end for service discovery components: EPFL QoS based discovery
WSMO Studio is partly funded by the EU IST projects DIP (FP6-507483), InfraWebs (FP6-511723), SemanticGov (FP6-027517) and SUPER (FP6-026850)
Come for more information: http://www.wsmostudio.org/
Recommend the tutorial