We used this one
http://www.stonedeckwest.com/installations.html in our display and it was not as easy as described on the website. There was no good way of starting the first row and we had to use adhesive, which was not descrubed on the web site.
I have seen photos where some builders have combinde wood or composite with stone. I think that is sort of a middle ground for people who like the look, but don't want to spend the money for an entire deck in stone.
right now, i'm guessing an entire deck, would run around $40-50 a SQ FT. but that is just a wag at this point.