A Peer-to-Peer network over an ad-hoc infrastructure is a powerful combination that provides users with means to access different kinds of information anytime and anywhere. In this paper we study the (re)configuration issue in this highly dynamic scenario. We propose three (re)configuration algorithms especially concerned with the constraints of the environment presented. The algorithms aim to use the scarce resources of the network in an efficient way, improving the performance and the network lifetime. The algorithms were simulated and used a simple Gnutella-like algorithm as comparison. The results show that the algorithms achieved their goals, presenting a good cost-benefit relation.