I used to download a lot of mods for oblivion, my favourite are any mods that improve textures, scenery or add more towns cities.
I also thought the overhaul mod which alters how characters and animals level up was essential. i like levelling all my skills to max, so i even got a mod for the previous fallout game to let all go to ten.
Are there mods like this for new vegas? or what mods are popular.for new vegas? plus what else do i need to get them going

You could easily find out yourself by searching the nexus' top 100 list for new vegas. Check it out man, it will really help you out.