Optically addressable defect spins in semiconductors are promising candidates for quantum memories. Merging spins and mechanics into hybrid quantum systems provides a route to engineering quantum registers and transducers. However, precise control of such systems requires a comprehensive understanding of each component as well as their mutual interactions. In this thesis we explore the imaging of surface acoustic wave phonons and their coupling to electron spins. We then present an overview of spin-strain coupling in silicon carbide divacancies, followed by fabrication and microwave characterization of Gaussian surface acoustic wave resonators on commercial wafer-scale substrates with a piezoelectric aluminum nitride film. The resonator's mechanical modes are measured optically using the point defect charge state’s sensitivity to electric fields that are piezoelectrically induced. Additionally, local strain and dynamic lattice distortions from standing waves produced by interdigitated transducers are imaged with nanometer-scale resolution using X-ray diffraction microscopy. Finally, we demonstrate all-optical detection of acoustic paramagnetic resonance with spin ensembles. Furthermore, we show magnetically forbidden Rabi oscillations for full ground-state spin control and use these resonant, coherent interactions with phonons for quantum sensing.