In a market, information about its specifications and the behavior of its participants is essential for sophisticated and efficient negotiation strategies. However, there is currently no completely researched system to provide and consult an overall knowledge of economic information in distributed markets. These markets are implemented for example by grid applications and gained importance over the last few years. This paper presents the economic information requirements and a high-level architecture overview for a decentralized market information system (DMIS). The proposed system acquires economic data in a distributed environment for providing it to individual traders or other participants in a decentralized manner. First, we outline the economic information requirements which the system needs to achieve. Therefore their properties and a privacy model has to be considered. Then we propose an architecture for the system which combines technologies of distributed information aggregation system and distributed publish-subscribe models, based on a structured overlay network. The architecture has been designed to meet both the economic information requirements and that of scalability and robustness of a large-scale distributed environment. Initial measurements confirm the proof-of-concept implementation of the existing prototype.