How does a cordless phone jack work?

I need to hook a phone line to my Directv DVR, but there is not a phone jack in the vicinity. Do these work and how costly are they?

It works by sending the signal through your AC outlets. It is preferable to use a real jack, but at worst the speed of retreiving the tv schedule will just be slower. Your local Radio Shack has this part.

I have used them before and they work great. They are like $30 and you can get them at wal-mart, Target, and Big Lots (RCA makes a model)

There are 2 units, one unit plugs in to the wall socket phone line and to the power receptacle and the other unit plugs in to your DVR and the power receptacle. I can't remember if there is any switches to set but its was fast and easy and there should be simple instructions to work with.