Throughout Link's quest he can eventually come acrossed Barnes who runs a shop in Kakariko Village selling Bombs although he wont start selling them until after the hero has saved Chief Darbus from the power of the Fused Shadow. Once the hero has acquired the second Fused Shadow Barnes will offer a Bomb Bag as well as bombs for sale.
Aside from Barnes's Bomb Bag two other bomb bags can be acquired from Iza and a Goron underwater at Zora's Domain. Additionally the hero can acquire a larger bag that can hold more bombs than the standard bag also given from Iza.
The most unique aspect of bombs is that there are three different types that the hero can purchase or find throughout the world. With each new type of bomb come unique properties although the basic use of the item remains.
One of these types of bombs is the Water Bomb were it can be used underwater unlike the standard bomb although it cannot be used while swimming normally. The bomb is modeled after a enemy fish that shares the appearance which have explosive properties and was most likely the inspiration for its creation.
The other type of bomb is the Bomblings a type of explosive that can move about independently and will explode once it makes impact with a wall or enemy. The bug has some homing capabilities were it will track enemies and go towards them to make using them easier although this feature isnt present when no enemies are present. Much like the Water Bomb this explosive is modeled after the real life version of the bug featured in the Forest Temple.
Additionally any bomb can be combined with the Hero's Bow to fire bombs at far distances and even can be used together with the Gale Boomerang to send the explosive to whatever destination the boomerang flies toward. With the Clawshot its possible to grab and bring a bomb towards the hero although this isnt utilized anywhere other than in the fight against Morpheel. Interestingly while the explosive is attached to the gust of wind from the boomerang the timer on the fuse will be reset and will not explode immediately unless it makes contact with an enemy or wall and this behavior is exclusive to the boomerang.