This guide is to help you get all those unique weapons in Fallout New Vegas. Or maybe there is just one certain weapon you want we’ll help ya find it.
Guns

Location#1: Sawed Off Shotgun (Big Boomer)

Place: Gibson Scrap Yard
To get this weapon you have to kill Old Lady Gibson. Keep in mind this will effect your stats so decide if it’s worth it or not. Sneaking by her or pick-pocketing her will not work. After you kill her search her persos for the Big Boomer.

Location #2: Hunting Shotgun (Dinner Bell)

Place: The Thorn
Right in front of the entrance to Westside is The Thorn, in there talk to Red Lucy and she will give you the side quest “Bleed Me Dry.” Only after defeating this quest will she give yoy the Dinner Bell.

Location #3: This Machine

Place: Camp McCarren

Location #4: Sniper Rifle (Gobi Campaign Scout Rifle)

Place: Sniper’s Nest

Location #5: .44 Mag Revolver (Mysterious Magnum)

Place: Sunset Sasaparilla Billboard
This one is delicate if you want to kill him be sure to do the side quest “Talent Pool” cause if he is dead you will miss out on the achievements, trophies, and gamerscores. After the quest is over you can kill him. One other way is to try and disarm him by shooting the gun out of his hands but be delicate, maybe have a previous save on hand for if things go bad.

Location #6: Cowboy Repeater (La Longue Carbine

Place: Camp McCarren
The one and only way to get this weapon is to kill Corporal Sterling so weigh your options, killing him will not make you popular with the NCR’s so decide if it is worth it to ya.

Location #7: .357 Magnum Revolver (Lucky)

Place: Primm at the Bison Steel Motel
Behind the cash register in the gift shop is a safe. You will need to have a lockpick skill of 75 to unlock this safe.
There are various magazines and books that can temporarily increase this skill to help you out if you’re not close to 75.

Location #8: Marksman Carbine (All American)

Place: Vault 34

Location #9: Varmit Rifle (Rat Slayer)

Place: Broc Flower Cave

Location #10: 9mm Pistol (Maria)

Place: Tops Casino

Location #11: That Gun

Place: Dino Mite Gift Shop
Either buy the gun here or pick the lock to the storage room and steal it.

Location #12: Mini Gun (CZ57 Avenger)

Place: The Devils Throat

Location #13: 9mm Sub Machine Gun (Vance’s Sub Machine Gun)

Place: Wins Hideout
This is in Vance’s safe in his shack. It is right down the street from H&H Tool Factory. Either by lockpick level 100 or with help with some mags and books you’ll need a level of 100 to pick it.

Location #14: BB Gun (Abeline Kid LL BB Gun)

Place: Field’s Shack

Location #15: Alien Blaster

Place: Hovering Anomaly
You have to start the game with the Wild Wasteland Trait to get this gun

Location #16: Gauss Rifle (YCS/186)

Place: Mercenary Camp

Location #17: Laser Pistol (Pew Pew)

Place: Sunset Sasaparilla Headquarters

Location #18: Tesla Cannon (tesla Beton Prototype)

Place: Crashed Veritbird

Location #19: Plasma Riffle (Q-35 Matter Modulator)

Place: REPCONN Headquarters

Location #20: Laser Rifle (AER-14 Prototype)

Place: Vault 22
First go to the fifth level of Vault 22. Off the elevator head to your right. Enter the Common Areas Stairway, the weapon is on the ground next to a skeleton before the next set of stairs.

Location #21: Pulse Gun

Place: Vault 34

Location #22: Euclid’s C-Finder

Place: Mick and Ralph’s
Melee Weapons

Location #23: Oh Baby!

Place: Charleston Cave
Begin moving through the cave destroying the Nightstalkers, take the path on the left and you’ll be lead to a area of water. head up the hill and there will be dead nightkins on the ground. The melee weapon is to the left of one of the bodies.

Location #24: Fire Axe (Knock Knock)

Place: Camp Searchlight

Location #25: Bumper Sword (Blade of the East)

Location #26: 9 Iron (Nephi’s Golf Driver)

Place: Samson Rock Crushing Plant

Location #27: Lead Pipe (The Humble Cudgle)

Place: Sealed Sewers

Location #28: Combat Kife (Chance’s Knife)

Place: Chance’s Grave

Location #29: Machete: (Liberator)

Place: Nelson

Location #30: Cleaver (Chopper)

Place: Wolfhorn Ranch

Location #31: Straight Razor (Figaro)

Place: King School of Impression
You’ll have to kill the hair dresser who is in the back room in the rear of the building. Like most of the others you will lose karma and standing so be sure to decide if the weapon is worth it.
Explosive Weapons

Location #32: Missile Launcher (Annabelle)

Place: Black Mountain
You’ll have to kill the Nightkin Sniper at the top of the mountain. Then go find his body to get the weapon.

Location #33: Grenade Rifle (Thump Thump)

Place: Nellis Aray

Location #34: Fat Man

Place: Quarry Junction or mountains south of Jacobstown
The first of the 2 ways to get the Fat Man is located on the edge of the southern part of the green pond in the quarry. Next to it is a skeleton. The other location is on a dead Super Mutant on the mountains south of Jacobstown.

Location #35: Frag Grenade (Holy Frag Grenade)

Place: Camp Searchlight
To get this weapon you will have to have the Wild Wasteland Trait enabled or else you can’t get this weapon.

Location #36: Grenade Machine-gun (Mercy)

Place: Dead Wild Cavern
Unarmed Weapons

Location #37: Displacer Glove (Pushy)

Place: Ruby Hill Mine

Location #38: Zap Glove (Paladin Toaster)

Place: Black Rock Cave

Location #39: Spiked Knuckles (Love and Hate)

Place: Bonnie Springs

Location #40: Bladed Gauntlet (Cram Opener)

Place: Camp McCarren
You can either kill or pickpocket Little Buster to get this weapon. He is usually at the front right side of the camp when you enter during the day. He is punching a bag over in front of the busted up yellow truck.

Location #41: DogTag Fist (Recompense of the Fallen)

Place: Cottonwood Cave
You can find it inside of Aurelius of Phoenix’s desk which is in his office on the second floor with a balcony.

Location #42: Boxing Gloves (Golden Gloves)

Place: Lucky 38 Casino
It will be at the VIP Bar above the Cashier Room which is on the left of the entrance.

And there you have it folks go out there and get them weapons.