The general site to get New Vegas Mods is the http://newvegasnexus.com/. The nvde mod is on there but you have to register as a member and allow for advlt content to be shown.
I would suggest playing the game through without any mods at least once. That way, you can determine what you didn't like or think should be improved and go from there.
There is one mod that doesn't affect gameplay but rather just has a bunch of fixes and that's the http://www.ravenmodding.terminal47.net/.It got continued from Zenball's work on the Nexus and is on its latest update. This'll give your experience a less buggy one so I would say install this mod and that's it for at least one playthrough. There is a version of it on the Nexus but I'm waiting for Loucifer to update it so its a bit outdated.