Resource information systems are a key component of Computational Grids. Centralized information systems hamper scalability and reliability, and thus, completely distributed resource information systems, based on Distributed Hash Tables have been proposed. In some cases resource distribution might be highly uneven, load balancing of data becomes thus a crucial problem. However, current load balancing schemes cannot handle large amounts of data corresponding to a single resource type. In this paper we propose therefore RESERV, a distributed information system for Grid applications with a novel load balancing approach, able to handle extreme load unbalance.