Tom,
My wife bought me a bundled program several years ago. Unfortunately it is outdated now and certain functions are glitchy on a win2k/winxp platform.
Nonetheless, it was very useful and lots of fun to play around with for room and garden design. It was the Broderbund Total 3D Home Suite Deluxe.
I think they still make some version of it. The other consumer grade program that i've heard is not bad is something by Sierra but i'm not sure they make it anymore. I googled up
this page which might be helpful.
This page also has a list.
