Dan makes a very important point in that advocates need to fully understand what is possible under current zoning codes. If you understand the barriers you can start to make rational suggestions for code amendments. Right now it appears that a collection of small homes on an single lot would be prohibited so I wouldn't begin to entertain the idea of buying land. There needs to a blueprint (or several depending on goals) so that everyone understands the end product . Is it a village in a semi rural area or a few tiny homes on a urban lot? Temporary (mobile) versus permanent?
Searching and finding possible land won't be as difficult as changing codes and gaining political,departmental and community support.