The thesis aims to investigate select problems of practical interest in plasmonic systems primarily from a viewpoint of guided wave dynamics. After providing theoretical foundation of the fundamental concepts, it re-examines the problem of quasi-static resonance in plasmonic nano-particles and demonstrates its equivalence with the standing wave model. Thereafter, it presents an approach to designing cylindrical metallic antennas tailored to sustain resonances at both fundamental and second harmonics for enhanced nonlinear frequency conversion. Lastly, it visits plasmonic slot waveguides with a view to identify the possibility of phase-matched interaction between fundamental and second harmonic which is necessary for steady nonlinear frequency conversion.