I assume you're asking about a meter for small appliances that plug into 120 V receptacles. Fortunately, there's a really neat meter for the purpose, and it's less than $25.

Froogle "kill-a-watt" -- you can't miss it.

It's a digital meter that measures RMS voltage and current, frequency, power, power factor, and VA, and it's become an indispensable part of my tool kit.