I'm in Novac, just went to REPCONN and I'm disappointed on the amount of upgrades i've found. I have the night scope and silencer for my varmint rifle which is getting phased out. I have a combat rifle, cowboy repeater, 10mm pistol and sub, and just got a hunting rifle. Only other upgrade i've come across is an extended clip for the 9mm pistol.

oh and also i would like to know where i can get stuff to make bullets! i can't find large pistol primers

Try gun runners, they get different upgrades constantly as long as you wait in between visits so they can restock. g/l

I haven't run into them yet, where do I find them?

Found Freeside East Gate yet? FT there and follow the chain-link fence on the left and you'll walk right passed the store booth

no i'm in Novac, i've gotten no further then getting to REPCONN. I can wait for my muffin though.

Hopefully, http://fallout.wikia.com/wiki/Fallout:_New_Vegas_weapon_mods will help you, and give you some of the information you need.