You must have the WILD WASTELAND PERK and go to tumbleweed ranch and around where you would normally find the rare gauss rifle you will find aliens in which you must kill to receive the Alien Blaster
You can't
Sadly you cannot get anymore ammo for the weapon anywhere else in tho mojave or surrounding areas :(
The only ammo you get is where you get the Alien Blaster. But apparently there is more ammo near a truck where a Mr. Handy is. Hope that helps. :)
alien blaster but ammo is hard to find after you have it all and its at the alien crash site
On the mother ship zeta expansion pack, if you don't have that you can't get them, besides one alien blaster with limited ammo at a UFO crash site
The normal alien blaster is at the site of the alien space craft. There is a grid of power lines west of minefield. follow them north until you get the alien radio signal, i forget what it is called. Then go off to the right a little bit and you'll find the space craft and the alien blaster, along with about 110 ammo for it. The fire lance alien blaster will be found at a random location selected by the game. I was lucky enough to get mine at the super duper mart. The radio signal is called Recon Craft Thefta Or, North of Minefield
After you complete Mothership Zeta and return to the Wasteland, you will find the blaster in the exact place where it was before. If you fast travel to The site and keep walk past all the crap left over and you should see a dead alien with a Blaster and ammo
MF Cells, 5 cells per shot
In my opinion Fallout New Vegas is. In Fallout NV it is easier to make caps so you can buy better wepons and ammo. In Fallout 3 It's hard to make a lot of caps in the begining making it a slow start. But is you want to test your skills play Fallout 3.
Definitely the Trail Carbine. But the ammo is hard to find, and is expensive. :)
When you start at goodsprings go to the general store they'll have some guns. Also if you follow the quests someone will give you a gun and some ammo. Oh and don't forget to look for some traveling merchants.
Lincoln's Repeater uses .44 Magnum ammo.
theres obvioulsy some at the crashsite where you can find it but if you need more there is some at fort independance [outcast controlled] and theres also some in the dlcs broken steel and mothership zeta available on PC,xbox,ps3