Here is another device you can use to find hidden cameras all around you. The Pro Extreme Wireless Camera Hunter comes with a 2.5″ color TFT high resolution display. It scans the commonly used video frequencies in less than 5 seconds (from 900MHz to 2.52GHz). The device has auto and manual scanning modes.
You can use this device to identify cameras from up to 500 feet away.
[where to get it]