In this paper we present a framework for forming interests-based Peer-to-Peer communities using client-side web browsing history. At the heart of this framework is the use of an order statistics-based approach to build communities with hierarchical structure. We have also carefully considered privacy concerns of the peers and adopted cryptographic protocols to measure similarity between them without disclosing their personal profiles. We evaluated our framework on a distributed data mining platform we have developed. The experimental results show that our framework could effectively build interests-based communities.