The Higgs field occupies everything in the universe. It is visualized as molasses that drags particles that move through it. Particles that interact with the Higgs, receive mass. So electrons that hardly interact with the field have very little mass, and protons and neutrons that interact with it regularly have more mass.
The god particle's existence was proved in the Large Hadron Collider at CERN. There are protons that are smashed together to relesase energy; since Einstein's theory of relativity states that mass is energy and energy cannot be destroyed, new particles are created from the release of energy. The Higgs is unstable, therefore it splits into more particles. The sensors in the collider detected this rare occurrence. It is rare because there are trillions of collisions occurring.