Alternatively alternativey: Raid Black Mountain, sell the stuff at Gun Runners, use [wait] for 3 days and 1 hour, then fasttravel back to Black Mountain and kill and loot all over again.
Rinse and repeat.
Yup, go for that one. At low level, with leather armor and a Cowboy Repeater.
Some areas which a low level character can actually handle:
There's several Viper camps along the road between Nipton and Novac. Relatively easy kills if you get the drop on them, and very decent loot.
Raided Farmstead has a large group of Vipers. I advise having Boone along; his rifle can be great help there.
If you don't mind a challenge, Morning Star Cavern offers some great loot. There's a Nightstalker pack outside and another one inside, but the inside pack is all about the Den mother; kill her, and they won't attack anymore, they'll just run back and forth. Be very careful with the outside pack; one on one they're not hard to kill but if they swarm you, you're dead. I suggest Explosives; Mercenary's Grenade Rifle makes short work of them.
Walking Box cavern- same thing, a pack of Nightstalkers outside and two separate small groups inside. Loot includes a set of Combat Armor.
Crescent Canyon has some Golden Geckos. Easy kills, fairly valuable hides.
REPCONN Test Site and REPCONN Headquarters both offer plenty of XP and loot, at relatively low risk.
The Fiends offer the best XP/loot balance though, and you earn good karma, too. There's a group of them near the Allied Technologies offices, although nearby NCR patrols may steal your kills.