You can buy them from http://www.streakwave.com

They come with a power supply and a POE adapter, that sends the power up the ethernet line to the unit. Just plug the other end into the computer. You can set up security so no one can "steal" your signal, no problem. If you need any help setting them up, my email in profile is good. Get a pair of Nano Loco 5. I think they are $69 each.

I am in the process of setting up a network with 6 Nano Loco's and some Axis video cameras here at work.