It's free, so what are you waiting for? Make sure your computer has enough horsepower to run all the cameras you want by verifying the system requirements on the download page.
The easiest way to try Vitamin D Video is with a webcam. You can even use the one built into your laptop. If you already have a network camera set up, it's really simple to configure it with our software.
Now's the fun part. Turn on the software, and it will automatically start looking for people and recording clips. If you need any help, the Getting Started section is a good place to, well, get started.