Service discovery is an essential component for distributed mobile applications in vehicular communication systems. While there have been numerous service discovery protocols, applications for vehicular communication systems pose additional requirements: discover services according to geographical position inside dynamic mobile environments. In this article, we propose a geographical location aware service discovery mechanism for vehicular ad-hoc networks (VANETs). The proposed mechanism exploits an IPv6 multicast service discovery protocol on IPv6 GeoNet-working specified by the GeoNet project. Thanks to the GeoBroadcast mechanism, it efficiently propagates service discovery messages to a subset of nodes inside a relevant geographical area with encapsulating IPv6 multicast packets. We implemented the proposed mechanism to the ns-3 network simulator, furthermore we integrated the prototype system using CarGeo6, an open source implementation of IPv6 GeoNetworking, with openSLP. Our simulation and real field evaluation results show the system can discover services with low latency and low bandwidth usage in VANETs even via multi-hop.