Home Audio Networking - General Question.

I have been looking for a nice, and inexpensive way to network my house's various amps, speakers and other computers so that when I decide to play somethingon one of them, I do not need to blast it loud enough to hear on the other side of the condo.

The thing is, most of the ones I have been seeing, Slingbox, and the Sonos (I think) are great, but pretty expensive.

Is there any way to link up several computers so they play the same music at the same time?

Is there a way to broadcast this signal to an independent speaker/amp set up in another room w/o having a computer or a $300 node?

Current setup has my "media machine" hooked up to an amp in the liing room. A previously hooked up Klipch 2.1 in the dining room, 2 machines and an amp in the "Office" and a pair of wireless in the bedroom hooked to the office amp.

Any suggestions would be welcome (Software/hardware, etc).

PS, the condo is pre-war, so going through the walls is more than a little difficult.....

TIA!

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