Grand Theft Auto IV/Weapons

In addition to finding them around the map, or receiving them from other characters for specific missions, Grand Theft Auto IV's Weapons can be bought from a few different places. There are three underground gun shops on each of the three main islands of Liberty City. You can also use Little Jacob as a source for guns and ammo once you've gotten his friendship statistic over 80%.

In Lost and the Damned, you can call Terry Thorpe for weapons, and in the Ballad of Gay Tony, Armando Torres. Aside from a few differences, they sell weapons as the same price as Little Jacob.

WARNING: If you use up ALL the ammo for a weapon, Niko will drop the weapon and you cannot pick it back up. This can be pretty costly if it is an expensive weapon, so make sure that you do not fire the last round of ammo for a particular weapon if you do not want to lose it.