tracing hiden electrical wire

The wiring in my house seems to have been done by a drunk. The materials are ok but the polarity is random and the central grounds are not connected though present in the wire used.
I would like to correct the polarity and properly attach all the central grounds. I will also be running seperate circuits for refrigerator etc as well as to kitchen with GFI's.
I have seen computer network people inject a signal into a wire and follow it all over a building. I would like to be able to do this and beleive it would make the project simpler.
When I was young my father did something simular with a cd radio. Is there any way to do this without buying lots of expensive equipment.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.