Yep - everyone who participated in the battle in some form or another and would be granted EXP Points will receive experience.
If you've got other questions in future, you can pop into the Questions Thread at the top of the forum here. Hope to see you around!
Exp. Share breaks up experience between Pokemon, but it gives both Pokemon the same number of EVs. In your example, the Pokemon that KOed Snorlax would get 2 HP Evs, and the Gible would get 2 HP EVs.
Also, in addition to the Q&A thread, [member]Rusticks[/member] has an EV guide, found in the Index of In-Game Guides sticky.