Need help with telegraph history

I need someone to point me to a book or website that will provide information on the various old western US telegraph lines. I'm not looking for technical information. Specifically, a telegraph line was installed in 1866, in Virginia City, Montana Territory and I need information about where that line connected to, probably Salt Lake. I figure there must be some type of map of all the telegraph lines in the old west for different years? I've searched the web all day with no results.

Thanks,

http://historywired.si.edu/detail.cfm?ID=324

http://www.telegraph-history.org/transcontinental-telegraph/index.html

Thanks Cliff and that verifies my guess about Salt Lake City. Wonder if there are any maps out there showing the telegraph lines and various towns?

I saw ones for the military, but thats all.
Use google image search. That may help.
https://www.google.com/search?q=telegraph+map+offer&rlz=1T4GGNI_enUS538US538&tbm=isch&tbo=u&source=univ&sa=X&ei=azh_Ur-iLpDyigLq5YCoBg&ved=0CDsQsAQ&biw=1298&bih=525

Good suggestion, Cliff. However I checked the LOC for telegraph maps and they had 15 that didn't pertain to what I need, wrong locations, wrong dates, etc.

Getting closer.