Simply copy my esp file in your" \Steam\SteamApps\common\fallout new vegas\Data" folder the esp then shows up in NMM.
I am actually pretty astonished/shocked what NMM seems to do to people. It's basic modding practice to copy the esp in your data folder. If that trends continues no one is able to mod their game anymore without NMM simply because they don't know better. That's a development I don't like at all.