Hi,
I'm looking for a website that sells good, inventive cat tree's.
Possibly custom or already made if suitable.
I'm really after ones which have tunnels as well as levels to climb.
I saw one on an American tv show the other day that had the base like a hollow tree trunk that the cat could sneak into and climb up inside to appear on one of the levels.

Any suggestions?

I got my (ceiling) cat tree from here - http://www.zooplus.co.uk/shop/cats/scratching_posts

Must say though, the tunnel is only part of my tree I've never seen my cats use.