I saw in your description that this item doesn't come with a power adapter and that you are unsure of input voltage? Does that mean I have to find a compatible power brick to use this item, or does it get its power through the USB cable?

Customers have reported success using via USB port. You can optionally use a power adapter (not included) if the amount of power coming from the USB port is not enough. USB 2.0 port is recommended over USB 1.1. There is a greater possibility you will need an external power source using an older USB 1.1 only port.