looking at having a few cameras outside of my home for security.. i was wondering if anyone made a system where the camera had a motion detector built in it, to where it could start recording anytime the detector went off?
That's a fairly common request. The solution is not in the camera but in the recording device. Security cameras don't turn on and off. They're always on. It's the DVR or PC that starts and stops recording. Most can be set up to trigger from a standard, outdoor motion detector.
Another popular technique for controlling the recording is video motion detection. At the DVR you program one or more "sensitive areas" in the field of view of each camera. As long as the scene in that area remains unchanged the DVR will either not record anything or take slow motion images. When something changes the DVR switches to "real time", recording full motion from that camera for a while before switching back.