Some information please

I would like to get some info on how to measure the following:
Power factor,
True Power,
Reactive Power, on a single phase line.
The monitor will sit between a single phase supply and a single phase load, the load could be an AC motor or a CFL.

 

[busbar]

From:

http://standards.ieee.org/

IEEE Std 1459-2000 Trial-Use Standard Definitions for the Measurement of Electric Power Quantities Under Sinusoidal, Nonsinusoidal, Balanced, or Unbalanced Conditions

This is a trial-use standard for definitions used for measurement of electric power quantities under sinusoidal, nonsinusoidal, balanced, or unbalanced conditions. It lists the mathematical expressions that were used in the past, as well as new expressions, and explains the features of the new definitions.