Is is true that if you live in the U.S, the only Vietnamese channel that you can get is VTV4? Does anyone have VTV channels at home?

i doubt it.
There will be some protests if they are going to be shown.
But you can always watch VTV channels online if you have access to fast internet. Type "VTV Online" or "Vietnam Television" in google to know more.

Try these links

http://www.vtc.com.vn/

http://www.vtv.org.vn/home/

http://vnntelevision.net/
(backups of last 2 or 3 weeks' pgms from all VN channels: films, musical entertainment, kiddies pgms, ...)

Listing of programmes
http://www.saigonnews.vn/snc/content/view/full/148

VTV4
is DTH (Direct To Home from satellite, captable with a parabolic satellite dish)
using DVB coding (Digital Video Broadcast, needs a DVB tuner)
could be also proposed on a cable TV network

Australia's SBS network used to have VTV but some people choose to moan really loud so SBS don't broadcast it anymore.

Thanks for the info, guys.