If you mean ship models and then into game? Your best bet is to read Drizzt's ship making tutorial.
To make guns, only as in the scripting (not new gun models) - your best bet is to read the tutorials forum on making a gun.
For putting a ship in the game (one that you have made) - its best if you read the tutorials forum, or alteranatively use Crabtree's ship scriptor.
You may have spotted a theme in these posts. If you read the threads stickied in here, you will find vast resources at your fingertips - all telling you how to do things. The only thing
you need to do is actually sit down and read them. If you get stuck, then ask - but you will not get people doing all the work for you - because you will learn........nothing.
If you need to know how to decrypt and open files - see the stickies at the top of this forum
Hope this all helps, as the only one who can do this is yourself