I'm sorry, are you asking if you can use other peoples ships for your set? If so, there is no known ship image data base. However, if you want to use someones images, you simply ask them, and most of the time they will approve your request with the understanding that in your read-me file you give them credit for their work.
Otherwise, if you want to make your own set, you can use the DOGA program. Many of use have, and if you do a search for it, you should find several links about it.
As far as unused images go, again, I do not know of any data base. However, I do have a few floating around my self. Mostly Trek images that I did not use. Some Doga ones.
[ 22 April 2002: Message edited by: Atrocities ]