http://www.sketchup.com
Being in architecture this software suits me well, but I was thinking it might be a good investment for beginners as well. 3D Max can be very overwhelming to new users who have absolutely no modeling experience. This software is basically a piece of 3-D sketch paper. Very simple to use, 8 hour demo... etc... They also have online video tut's which make learning the program very easy. It also has full import/export features for raster images, .avi's, max, dwg/dfx and vrml.
another great program is wings 3D... for more organic shapes.
Pretty simple to use also...
http://www.wings3d.com