The question you are asking is a bit unclear in my eye but I'll try to help you.
You can only make weapons look like the ones that are already in the db => the ones that are in WoW.
If you are searching or need a displayid then I suggest you use:
http://wow-v.com/displayid-finder.php.



You can also use WoW-V to make various WoW related items:
http://wow-v.com/create.php.

(Note, you need to be signed it to use these.)