??? about cheap(?) artificial waterfall

It seems like there should be some cheap plastic waterfalls
available, or at least something that can be used as one.
I'm just looking for something about 3'-5' tall. But so far
everything I've found is several hundred to a thousand
dollars. It's just plastic, and doesn't seem like it should
be worth much more than a good bucket or plastic storage
container. Are there any cheap waterfalls, or things that
can be used as one? Some of these look like they might
work:

http://rock-n-water.com/landscape_di...ff_catalog.htm

but without having checked the prices yet I'm afraid they
will end up being too expensive...they just have that
look about them. Does anyone have any advice or
suggestions? Maybe I could make my own thing, but
I'm afraid the number of rocks it would take would make
the whole thing too heavy and impractical. Any suggestions
on something like that maybe?

Thanks!
David