Hoping someone can help me- I'm interested in building a square or
rectangular pond on my pool deck. I just moved to Naples Florida. I'd like
to find a pre-formed tub and build a face for it. My problem is where to
find a large tub in the area.

Size?

Anyway, you don't need to use a preform. You can use flexible pond liner.
What you do is build the form (which has to be very sturdy), line it with
plywood, then a seal of some sort, then the liner. You may have to eventually
replace the liner, but not for a long while.

When I wrote this, I was assuming you wanted a wood frame pond. If you don't,
my answer would be a bit different.

Anyway, look he

http://www.wetwebmedia.com

C//