Help counting posts and threads in catagories

[uReside.com]

I need to know how to have my catagories count threads and posts, and who the last was to post, just like a forum. My site is divided by states, area of the states, cities of the area, and apartment complexes of the city, and i dont want people to be able to make new threads in anything but the apartment complexes, but there are 3-4 levels before you get there.

Texas (no threads)
--Dallas Ft. Worth (no threads)
----Irving (no threads)
------AMLI at Valley Ranch (can post here)

someone help!