i downloaded d3d9.dll just to increase the games performance but it says to put it in the FalloutNV data folder. i bought this on direct2drive and cant find the folder. Ive looked for a way to add it through steam but cant find a way on there either. If anyone knows a way i can add this that would be great.

That isn't considered a mod and doesn't go in the same places as mods do. That file needs to go in the folder with your FalloutNV.exe file. More than likely:

c:\program files\steam\steamapps\common\fallout new vegas