What do you mean by "3D" exactly?
The best value in all cases is probably one of the HD6000 series, depending on your exact need.
I'm willing to bet he means nVidia 3D vision, which would rule out Radeon cards. I totaly agree with that the value on the Radeon HD 6000-series cards is where to go.
But do they support AMD HD3D? Because that there could be his solution.