Rather obvious but thought i would list the weapons below. You can see your progress of this on your stats page (back button on main title screen). To be honest most will come naturally when levelling up the weapons to level 10 each.
- Baseball Bat
- Hand Cannon
- Assault Rifle
- Bazooka
- Shotgun
- Plasma Blaster
- Sheep Launcher
- Rocket Shield
- Sentry Launcher
- Hammerhead
- Grenade
- Holy Hand Grenade
- Banana Bomb