Consider the unique benefits of stalking in the 21st century.
You can leaf through pages and pages of photos of your target... that they have uploaded themselves for your convenience. You can see their answers to "What are you doing right now?" at any time - day or night.
Your target helps you maintain constant surveillance by utilizing GPS check-in with Facebook Places and FourSquare.
It's a relative golden age. You can even stalk from home if you want.