uhhh...actually there are some weapon skins in a post on here by lightsith in the thread "Everyhting you need. (models, skins etc)" should be on the second or third page of threads. But anyways, you said that the weapon wouldn't disappear, well since between the time someone picks up one item and drops it again, someone else probably picked up another item and his weapon would be the last created effect. The only way you could make your idea work is if you made the item "CAUSE" the special effect. You can do that in object editor by clicking the item tab, choosing your item - look at what ability it uses (ex. orb of fire uses - item attack fire bonus) find that ability in the ability section and change the Art - Target to the skin fileof the weapon and change the Art - Art target attatchment point to "hand" or whatever its supposed to be. When the char picks up the item the ability activates and creates the effect. When the char drops the item then the weap effect should dissappear. If the weapon doesn't use an ability and is there just to look pretty, then you can create an ability called "weap pic" or something like that and have it do nothing "but" make the special effect.
Yep that should work, if it doesn't then PM me or post it in here and i will try it myself and try to fix it.
I hope you understand all the stuff i just said, sry if its sloppy.
Good luck man.