The book contains two "base classes"
The Archer
The Archer-Ranger
(and these classes also suit other ranged combat archetypes, including javelineers, crossbowmen, and so on)
A selection of character backgrounds (basically ways to tweak these two base classes to suite character ideas like the young soldier, tribal hunters, and so on).
Multi-class character paths for the Urban Hunter and Warren Guard.
A selection of archer-based Prestige Classes
27 Archery and Ranged-Combat feats
New arrow types, crossbows, and equipment
Rules for bows larger and smaller than the standard PHB weapons, including composite bows, and exactly how "mighty" a mighty bow can be based on the size of the weapon (medium composite bows can be mighty +2, whereas gargantuan composite bows can be as powerful as mighty +14)...
And 9.5 pages of magic items, primarily magic bows and arrows.