Can I use a 11.1V LiPo directly on 12V electronics?
Is it safe to tap a line directly off the battery for each or do I
  need regulators of some sort?


"Tap off the ESC" probably refers to a BEC; it is designed to, at least minimally, protect its own load from the inductive loads. Wiring a resistor between the battery and your camera is not wise, but also (I'm assuming) not what you really meant.

A common BEC(regulator) between them is fine; consider using a buck-boost type to keep a steady 12V regardless of Vin.