The last two use multiple layers in the shape of the entire water area. I usually use a PS filter called Render Clouds using a light and a dark shade. Sometimes I'll run a filter called Difference Clouds over that. I'm not sure *exactly* what that one does technically but visually it makes the differences in coloration more dramatic. I simply mess with the transparency of these layers until I come up with something that approximates what I want. Generally I make the deeper layer colors muddier and the upper layer colors bluer and lighter - outdoor water looks best to me when it's reflecting the sky. Over all of that I will usually use a layer with Render Clouds and then use the Ocean Ripple filter and put that on top (sometimes Overlay, sometimes with Soft Light or something else that looks good).
I may have used a mask with partially transparent edges to make bits of the darkest water layer go away so you can see a little bit of the bed/ground beneath. On the ground itself I painted that fully, just like the land, with dirt, sand, rocks, etc. In the one with docks I think there might even be some sunken boats and crab traps and things...but you really can't make them out.
The whitecaps are simply done by selecting the water shape, creating a new layer, reducing the size of the selection (in PS it's Selection->Modify->Contract I think) by a few pixels and then stroking with white and repeating until it looks good - I varied the size of the reduction and the stroke size each time. Once done I used the smudge tool and eraser with a grunge brush to muck it up until it looked good.
On the map with "Tarina" on it I also used a couple of Hue-Brightness adjustment layers with masks to get that bright sea color...because it didn't really come out right from my color selections.
Just remembered I did one of water in a cavern here (room D):
http://www.cartographersguild.com/al...chmentid=31905
There's also some crazy, shiny polluted Gamma World water here, but I doubt it's of much use to you!:
http://www.cartographersguild.com/al...chmentid=31907
Hope any of this helps.
M
Edit: On slippery, gradual, here's a bigger zoom in of the ruined bridge map:
http://www.cartographersguild.com/al...chmentid=34353
It actually is a fairly gradual entry to the water (you can see better on the full-sized map but...) and you can see some of the bottom near the edges, less towards the middle of the stream. Same techniques, maybe with more masking of layers since I wanted to show more of the bed. I actually botched up the shore line some in this one...trying to make it seem as if the water was lapping around the rocks there. Didn't really come off very well.