Try a Magnum Dynalab whip antenna. It is essentially the same as a car antenna. I have also had luck with Godar Model 1:
http://users.mcleodusa.net/m/mgodar/.
The real solution is to install a rooftop, but that does not work for most.
http://users.mcleodusa.net/m/mgodar/.
The real solution is to install a rooftop, but that does not work for most.