What locations do enemies(humanoid, preferably legion) respawn? I'm running out of places to loot, so...

I know the Legion Raid Camp respawns, it's where you go to rescue the Powder Gangers that are being held there in the quest Booted.

Personally I'm villified with both groups so I just kill the Legion recruits and the prime and then I kill the tied up Powder Gangers too. Funny that the Powder Gangers respawn too lol, all tied up. Even if you free or kill them.

The powder gangers respawn too? Huh, didn't know that. I somehow ended up soft-hearted devil with them, I think because I freed them for the quest.

• Highway 95 Viper's Encampment
  
• Legion Campsite, on pip-boy, south of Highway 95 Viper's Encampment
  
• Raided Farmstead
  
• Legion Raid Camp
  
• Recon Legion Camp, on pip-boy, North East of Lucky Jim Mine

If you're on PC you can download http://www.newvegasnexus.com/downloads/file.php?id=35786, which will force all non-unique enemies respawn.
I'm crossing my fingers for a new version of MMM for NV though, increased increased spawns and feral ghoul raise made F3 so much fun.

Yeah it's pretty funny, they respawn all tied up kneeling on the ground, you can just walk up to them and put a 9mm in their face all execution style.

That's exactly what I did, but it was a 5.56 from That Gun.

Fiends outside of Vault 3 area, and they have lasers and plasmas $$$$