Recently developed dual port reflectometric spectroscopy (DPRS) not only enables detection of single electron charging events in nanoscaled MOS single-electron transistors (SETs) that are not detectable using conventional transport spectroscopy, but DPRS also provides the ability to spatially localize charging events and discriminate between charging events involving defects and those associated with the SET island. Here we present an experimental study of charging processes in Si single-hole transistors (SHTs) from deep depletion (prior to electrostatic formation of the island) through the initial stages of SHT island formation and population with the first few holes.