Click on one of the Advertising links on this site and order a new one?
Oh, wait, this is supposed to be a real answer not a facetious one.
Okay, let's break this into a couple of categories: lens versus camera, ocean versus fresh water.
Let's start with the bad news possibility first: camera dropped into any water. You have a minuscule chance of recovering a camera dropped into fresh water and no chance of recovering one dropped into ocean water. But to maximize what little chance you have: remove the battery IMMEDIATELY. On the D1 series, D2 series, D3 series, D4 series, and D5 cameras, that means the clock batteries, too. Electrical current plus water is a no-no for electronics. If it went into salt water, flush the camera with distilled water. Next, clean off all the water you can, as well as you can. If you know how to disassemble a camera, I'd do that and get as much visible water out of the insides as I can, but very few people would be capable of doing this, let alone in the field where it would need to be done. Next, put the camera in a warm, 0% humidity environment with as little open air as possible, and with all doors, caps, etc. open, plus with as many silica gel or absorbers as you can stuff in (e.g. rice). Wait two days minimum before doing anything else. If you're really lucky, not enough water got to the internal circuitry with power still active to start the corrosive processes that usually occurs. Ocean water (and some bad freshwater sources) have too many salts and contaminants and trigger corrosion pretty much no matter what. If that happens, the camera may be gotten to work for awhile, but the long term prognosis is terrible. Once corrosion sets in, the electronics are compromised. Nikon will not repair equipment with corrosion damage.
With a lens you have a slightly better chance, even with salt water. That's because it isn't quite as electronic, and the electronic parts can sometimes be easily replaced, if necessary. Indeed, older manual focus lenses may come through dunkings relatively unscathed, though if water gets between elements the lens needs to be disassembled and each element cleaned, then the whole thing reassembled. But the same is true for lens as well as cameras: remove power immediately (get the lens off the camera, as the camera is the power source), dry as much as you can, put into a 0% humidity warm environment with as little air as possible and as many silica gel packs as possible until the moisture is all gone. If you dropped the item into salt water, you want to flush with distilled water before trying to dry.
What, you don't travel with silica gel packs? ;~)