Thanks 911...

This 21 year old Wisconsin Madison student, Brittany Zimmerman, had someone break into her apartment. She called 911, and they didn't show up for 48 minutes... Her fiance came home to find her dead after being stabbed near the heart multiple times. The 911 operator claims that she didn't hear anything on the phone despite court records alleging that there were screams and gasps on the 911 tape. This slaying happened back in April, but they are now saying that she may have been able to live, had help come sooner.
Now, this bothers me because I remember thinking as a kid that the police show up maybe 3 seconds after you place the call. I think that's how I forced my brother to listen to me- by threatening that I will call the police and they would be there ASAP. What? Is that weird? Anyway, now that we are in the world of cell phones, can they locate where you are? If someones crazy ex girlfriend is choking me, and I call 911 from my cell, can they even find out where I am? And even if they can locate where the call came from, how long will it take them to get there? I could maybe last 35 seconds, and then just assume they aren't coming and give up. This story was depressing, but it does bring up a lot of questions.