Though I have played RCT 2, (Years ago), I am new to the RCT3 family, I have the Platinum package and am still playing with it. One of the neat things I noticed in the career mode in Soaked were pirate ships. I think I found them in the game's design sections, but when I tried to place one, it placed it UNDER the water. That would be fine if I wanted the effect of a sunken ship, but I don't I want it to float on top of the water. How do I achieve this?

Save it as a structure and try it.

Like objects you want to place in the air, hold shift and drag it up until it's where you want it. To remove the supports, download and install a support killer. Custom scenery is a big part of making successful parks/rides/structures in RCT3, so google some and try installing it. A good set for a support killer and some other basic CS is DazMatze Utilities. It can be downloaded at http://rctgo.com/downloads/view/4120. Unzip the file and copy it into the Atari > Roller Coaster Tycoon 3 Platinum > Style > Themed folder. Then, when you go into the game, you will have additional scenery. Go to the DasMatze Utilities folder under scenery, select 'support killer', and place it on the squares that the ship sits on. This will remove the ugly supports you can see through the water. After this, I suggest you look into other CS, especially custom supports. Get/install Moby's Steel Jungle and look up a tutorial. Enjoy the game =)