Ok, finally home.
1. Get the water out of the bilge.
2. Remove spark plugs, but keep them in the boots.
3. A few different options, but here's what I prefer (needs at least one helper though): Stand the ski up on the nose and then tip it further over. It's best to get it as close to completely upside down as possible. Make sure at least one plug is touching the block.
4. Crank it until there is no more water coming out. (Shouldn't take long, even fully submerged)
5. Sit it back down, pour just a little bit of gas into the plug holes, reinstall plugs.
6. Tip the ski slightly so that the exhaust side sits lower than anything else.
Crank. It should fire right up.
If you have a helper or two, you can get all this done in less than 10 minutes. No special tools or lighters needed, fires right up. Key is to get all the water out and keep it out (hence tipping it in step 6).
We've done this multiple times over the past year now and it never fails. Keep an open mind and give it a try next time. I'll try heating the plugs next time it happens to me to see how it works.
PS: If you suspect you have water in the gas tank, let the ski sit for a half hour. Remove the reserve line (or whatever line you have sitting furthest to the bottom of the tank) from the carb/whatever and direct it outside the hull. Then blow into the vent line to pressurize the tank. You can stop when you see gas coming from the line instead of water.