The Marked Men, Cheeky, Witch Hunt, Adelitas, Resist, Surrender, Gruk, Hook & the Daggers, Czolgosz, the Soviettes, This Bike Is A Pipe Bomb, the Tim Version, Moral Crux, Rager, I Object, Dillinger 4, the Bananas, Vena Cava, Mika Miko, Harum Scarum, the Exploding Hearts (r.i.p.), the Cute Lepers, Gorilla Angreb, the Spits, Underground Railroad to Candyland, Death Crisis, Randy, Defiance Ohio, Toys That Kill, Prizzy Prizzy Please.... I know I'm forgetting some but there you go.
Almost all of these bands have released awesome underground punk rock records within the past 3-4 years. Some are a little bit older, but are still great bands that are ridiculously underrated.