This thread is pretty old, but I stumbled upon it so I figured I'd address it.
Walking sticks? Endangered? I highly doubt it. They're everywhere around here (central Arkansas). Granted, most people don't see them very often because they're so well camoflaged, but I usually see 20 or so every year... and I'm not even outdoors all the much any more.
Example : This guy ended up on me somehow while dove hunting... scared the shit out of me momentarily when he crawled over my hand. He must've fallen out of a tree or grabbed on from a branch I rubbed against.

-darc
EDIT: We're talking about the plain ole North American walking stick, beckdg pointed out to me that there are a lot of crazy ones from (mostly tropical) other areas. But, the one in the picture above is very common around here.