I'm a CS master's student at Stanford, which means I don't get funding automatically. But with a 20 hr/week assistantship (TA or RA) I get my tuition refunded, which is about $8200, and a roughly $7000 stipend. That's for one quarter (quarters are Sep-Dec, Jan-Mar, Apr-Jun). It's enough to cover housing, food, and a little extra...but it's certainly frugal living.
In the sciences 20kish per nine months. Presumably a few thousand lower in the humanities, but I'm not sure. It's actually not that bad. The area is expensive and I can't afford a car, but it's enough to live comfortably.
What are typical graduate student stipends these days at Stanford? I have no idea.