The kind of poetry you are describing is called Concrete...a funny term
I always thought. However it is really fun and can be quite complex as
you mention. I use it with history quite a lot, we have had great
continent poems using this method, we use all kinds of information to
make the shape of the continent, not just the word, Asia for example.
One might list as many of the countries as possible in the appropriate
place if possible.
Now that you bring it up, I will probably do it the US states as I am
quite a state jag. The cookies that they made in the shape of states
were very creative, and HUGE! We all were a little queasy after eating
our creations. I guess those were culinary arts poems :)