[villagetinker]

There is a stained glass club, todays daily sun has the recreational news, it may be listed there. IMHO. you may want to have a piece of plate (window) glass in front of the stained glass so that it is protected from the water, like the way the front door windows are made.
It sounds like you have a design in mind. if not you might look at a pet store for the aquarium background. These are plastic cling design, and could easily be placed on a piece of glass for your background. Also, you can check at the local craft stores (Michaels, etc.) they may have info on local crafters. Finally, I think there was a stained glass person at the merchants on the square events.
Hope this helps.