Research into human computer interface (HCI) has been very active in recent years due to the advances in software applications. Such devices are aimed at providing a more natural interface for which humans to interact with machines. In this research, we propose a new approach to the development of a touch interface through the use of a surface-mounted sensor which allows one to convert hard surfaces into touch pads. We first develop, using mechanical vibration theories, a mathematical model that simulates the output signals derived from sensors mounted on a physical surface. Utilizing this model, we determine the hardware required for this research. We then develop a source localization algorithm based on an all-pole filter model for location template matching that extracts the dominant frequencies of the tap. The performance of the proposed algorithm is compared with existing approaches and verified both in a synthetic as well as a real environment for the localization of a finger tap on a touch interface. In addition, we explore the time-difference-of-arrival based methods for source localization and implement a real-time wireless source localization prototype.