Spin torque oscillators (STO) were developed in 2003 and since then great progress has been made in understanding their underlying physics, frequency of operation, frequency tuning range, and functionality. These nanoscale oscillators with their octave spanning frequency tuning range have been touted for many applications including neuromorphic computing, magnetic field sensing, and microwave signal detection. Since their inception, output power of spin torque oscillators has been improved by five orders of magnitude. In spite of all these developments, the adoption of spin torque oscillators as extremely tunable signal source has been hindered due to their large linewidth and frequency stability issues. Solutions such as using spin torque oscillators in a PLL and injection locking of spin torque oscillators has been demonstrated. However, these solutions need an external signal reference for their implementation. Recently, self-locking of spin torque oscillators to their amplified, delayed output signal has been proposed and initial experiments have demonstrated an encouraging progress in the improvement of the linewidth. Further improving on this concept of self-locking, we propose a system that uses spin torque oscillators in a delay line oscillator with a high quality factor micro-electro-mechanical (MEMS) resonator as the delay element. This spin torque oscillator coupled with a MEMS resonator in a feedback system is presented in this thesis as a magneto-acoustic oscillator. This dissertation presents all the components needed for realizing the magneto-acoustic oscillator as well as addresses the issues and challenges in its implementation. To maintain the tuning capability of magneto-acoustic oscillator we use high-overtone bulk acoustic resonators (HBARs) as the MEMS resonator, as they have numerous resonances spread over large range of frequency. We fabricated and characterized one port, high-overtone bulk acoustic resonators to be used as stress transducers for strain feedback-based magneto-acoustic ...