There are 3 of them. The first is at MB - Main Retail Area Barracks 4 on the right Side of the Chamber.
List:
TL 5 Self-Constructed Trash Grenade (AoE-Weapon)
TL 5 Street Model Grenade Launcher (AoE-Weapon)
TL16 Unlabeled Hand Grenade (AoE-Weapon)
TL23 Grenade Launcher (AoE-Weapon)
TL24 Self-Constructed Spraycan Flamer
TL34 Defender Rocket Launcher (AoE-Weapon)
TL40 Unlabeled Gatlin Cannon
TL42 Basic Anti Vehicle Rocket Launcher (AoE-Weapon)
TL42 Tangent GL-253C Grenade Launcher (AoE-Weapon)
TL46 F24 Flamer
TL48 Rocket Launcher (AoE-Weapon)
TL61 Gatlin Rifle (dont ask what that is doing here, i wrote it at the Lowtech Rifles also though)
TL63 Gatlin Cannon
TL67 Ryker Rocket Launcher (AoE-Weapon)
TL70 Cleansing Flamethrower
TL79 Enhanced Gatlin Rifle (see above)
TL81 Enhanced Gatlin Cannon (if i remember it correctly this Cannon is WEAKER than the TL75 Tangent Speed Gun (City Merc Epic Item.)
The second Smuggler is in the Dome in the Tsunami Sector. He sells Hightech Cannons also.
List:
TL 5 Self-Constructed Trash Grenade (AoE-Weapon)
TL 5 Street Model Grenade Launcher (AoE-Weapon)
TL16 Unlabeled Hand Grenade (AoE-Weapon)
TL23 Grenade Launcher (AoE-Weapon)
TL24 Self-Constructed Spraycan Flamer
TL34 Defender Rocket Launcher (AoE-Weapon)
TL40 Unlabeled Gatlin Cannon
TL42 Basic Anti Vehicle Rocket Launcher (AoE-Weapon)
TL42 Tangent GL-253C Grenade Launcher (AoE-Weapon)
TL44 Freezer Cannon (Hightech)
TL61 HEW Burner RC275 (Hightech) (AoE-Weapon)
TL65 Enhanced Freezer Cannon (Hightech)
TL78 Raygun Cannon (Hightech) (AoE-Weapon)
TL90 Special RC13 Raycannon (Hightech) (AoE-Weapon)
The third Smuggler is in the Industrial Area Sector 1 in NC. Hes got only 2 Weapons.
List:
TL63 Gatlin Cannon
TL81 Enhanced Gatlin Cannon