Here's a few off the top of my head.
Nighthawk Customs - Berryville, Ark
Kimber ( Pistols ) are American Made
Les Baer - Pistols & AR's
Dave Lauck ( D&L Sports ) - Pistols & AR's
I think Wilson Combat are 100% American Made - Pretty sure on that one.
Any of the good custom rifle stuff:
Lawton Actions / Hart Barrels & Actions / Krieger Barrels / Mike Rock 5R / BAT actions / Bartlein Barrels / probably forgetting a few but it's early...
Badger Ord. Action & parts
Barrett Rifles - Pretty proud about their USA made stuff
Chey-Tac ( Probably going backrupt - but still all made at home )
There are several AR production houses that are mostly USA made parts and labor, but to name any would just lead to someone pointing out they get take down pins from Argentina or something.
Some more will come to me later I am sure...