Do I need to purchase specific hardware for ESXi 5.0 to work effectively
Make sure the hardware which you are purchasing is listed in VMware HCL
Just want to highlight the FREE version of ESXi supports only upto 32 GB Physical RAM but there is no limitation on physical RAM/ Cores
Are there any other vmware products that I would need alongside ESXi 5.0?
if you are going to use only Free ESXi there is no additional componenet required. Once yo have installed ESXi you can installe vSphere Clinet on your PC and start building VM;s
Can a Hypervisor be used with ESXi 5.0 rather than requiring an OS?
Not sure if i understand correctly, ESXi 5.0 is a OS which has to installed on the hardware