"Powerline" adapters extend your internet signal throughout your house using your existing power lines...but at what cost???

Serena Kharlukhi: Hi, my name is Serena Kharlukhi. How may I help you?
Eric Howton: Howdy!
Serena Kharlukhi: Hello Eric,
Eric Howton: I bought a Powerline HD 1GB Starter Kit today
Eric Howton: VERY excited to get internet to the back of the house
Eric Howton: Sadly, they only "connect" when plugged into the same room?
Serena Kharlukhi: Ok.
Serena Kharlukhi: Let me go ahead and assit you.
Eric Howton: That would be great!
Eric Howton: Because they don't *actually* work.
Eric Howton: Unless they're plugged into the same room.
Eric Howton: Which of course, isn't the idea behind why they exist.
Serena Kharlukhi: Please confirm if the model number of the Belkin product is F5D4076 v2000?
Eric Howton: Yes ma'am - more specifically, V2212
Serena Kharlukhi: Thank you for the confirmation.
Serena Kharlukhi: Did you try to plug in the adapters in the same electrical phase ?
Eric Howton: Like, temporal dynamics?
Eric Howton: They plug into the wall.
Serena Kharlukhi: Ok.
Eric Howton: When they're on the same wall or same room, they work
Eric Howton: When they're plugged into the walls of different rooms, they do not work.
Serena Kharlukhi: Ok.
Serena Kharlukhi: I will like to explain here the adapters will work when they are connected on the same electrical phase of the house, like a single phase electrical wiring.
Serena Kharlukhi: When you plug the adapter on a different wall socket of the same room do they work?
Eric Howton: As I've stated three times, yes.
Serena Kharlukhi: Ok so you are trying to use the other adapter in another room, correct?
Eric Howton: Awkwardly enough, yes.
Serena Kharlukhi: It could be a possibility that the wiring in the house is different in the other room as the adapters will only work in a single phase and the other room may have another electrical phase wiring.
Eric Howton: huh
Serena Kharlukhi: What I would suggest you is to check the electrical wiring on the other room from an electrician and confirm if the electrical phase is the same on all the rooms.
Serena Kharlukhi: Here the adapters will work if the electrical phase is single on all rooms, using same wiring phase.
Eric Howton: Thank you.  I guess in reality, these aren't the solution I hoped they would be.
Serena Kharlukhi: Well for the adapters if they are working fine in one room they will also work fine in other rooms but the electrical phase here should be the same for all rooms.
Serena Kharlukhi: Please check for the wiring once and get back to us if the electrical phase is same on all rooms.
Eric Howton: Interestingly, I require them to work in different rooms.  And re-wiring the house doesn't seem to be a viable financial option
Eric Howton: Thank you for your time.
Serena Kharlukhi: You are welcome Eric.
Serena Kharlukhi: I am sorry but the adapters works on a single phase.
Serena Kharlukhi: Is there anything else I can help you with today?
Eric Howton: No ma'am.  Thank you have a FANTASTIC day!!!
Serena Kharlukhi: You are welcome Eric.
Serena Kharlukhi: Thank you for contacting us!
Serena Kharlukhi: Have a wonderful time ahead.
Serena Kharlukhi: Bye!!

im single story Eric, but our wireless router works thru out the house and i can sit in drive or the patio and have great reception...? why the need for adapters?

This single phase thing is one major drawback of the powerline networking. And also, in theory, there are some houses wired to share the power with the neighbor (shoddy contractors and/or builders), so they would be able to use the information as well, if they have the same adapter system.

I have an Apple Airport Extreme in my upstairs office and nice reception in the backyard and front of the house. Maybe a more powerful wireless router would be a viable option. Re-wiring does not sound like too much fun.

The back quarter of the single-story house (the "North Wing") is where the children's LAN gaming takes place.  Why not wireless?  Throughput and connectivity, mostly.  Plus, I don't want to have to buy a bunch of O/S specific wireless network adapters.  When we switched my son from OSX to Win7 last year, I had to buy a new one - and neither of them would work on my daughter's linux box :/

I don't know how much the power line thing costs, but I reckon you could get a cat 6 cable run to the north wing through the attic for ~$50-60 - throw an old 100 Mb switch in the back and you're golden.