Basically, I want to bring the Dart-gun into FO:NV because my "assassin" style character in FO3 basically only uses that gun, and then superior versions of it over the course of the game. Since I don't think it's in FO:NV, I am wondering how I would go about bringing it into FO:NV.

Thanks for any help.

If the art resource isn't already buried in FONV (which is possible) you won't be able to bring it over from FO3 - removing content from one game to put in another is illegal. However even if you can't use the original dart gun art resources you can probably simulate the effect with another weapon.

Hey NinjaFish, the http://www.newvegasnexus.com/downloads/file.php?id=40007 mod has the dart gun and a lot more from FO3.