Nanoplasmonic materials are metals with nanoscale dimensions that possess strong localized electric fields at specific resonance wavelengths. Such a fascinating optical property can be exploited in numerous applications such as chemical and biological sensors, solar cell technology, metamaterials (cloaking technology), localized heating, biological imaging methods, etc. The ability to control and tune the plasmonic resonance of nanomaterials is critical, and depends strongly on the materials design and fabrication technique. For practical applications, the design procedures shall be simple and straightforward while the fabrication method must be scalable and inexpensive. In this dissertation, we utilize a simple, inexpensive, and scalable nanofabrication technique known as shadow nanosphere lithography (SNSL), which combines the nanosphere lithography with the dynamic shadow growth method, to design several new plasmonic structures/materials. Based upon the principles of SNSL, we introduce four specific strategies for designing plasmonic nanopatterns with tunable plasmonic properties: silver (Ag) films on nanospheres, Ag triangular networks, Ag double triangles, and Ag-Cu alloy nanopatterns. Each structure possesses unique morphologies that can be predicted through numerical simulations based on the shadowing effect of the nanosphere template. By systematically changing the nanopatterns morphology or material composition, the localized surface plasmon resonance can be tuned to specific wavelengths. The relationship between the nanopattern morphology and its plasmonic properties are understood through finite-difference time-domain simulation, while the effect of composition variation on the optical properties are predicted by an empirical equation derived from bulk materials. Finally, we establish that by tuning the localized surface plasmon resonance of these plasmonic nanomaterials, the sensitivity of these structures can be optimized for sensors based on surface enhanced Raman spectroscopy and localized surface plasmon resonance principles