In this paper we present the design and implementation of an agent-mediated B2C e-Marketplace as part of the social and immersive 3D e-Tourism environment “Itchy Feet”. Customers are able to interact in an intuitive way in the 3D environment and assess tourism products prior to purchase. The e-Marketplace provides services via autonomous software agents for the entire purchase cycle. Fair trade among agents is ensured by regulating the environment with Electronic Institutions.