That's good advice from Falsehope. In your case, consider this: first timers sometimes are too aggressive, which can be a turn-off for her. Fast and wild might be fine for when you've already discovered all of her triggers, it's bad for exploring.
When you first start having oral with a new pussy, you have to be very relaxed - not quite to the point of yawning, but go slowly. It's important for you to find a comfortable position, because you're going to be there for a while, maybe 15 - 30 minutes. You should make some loving noises too, she'll love that. If you get impatient, it can kill her desire to have you down there thrashing around.
Like you said, you know where the clit is supposed to be, but it's not well defined on some women. As you move your tongue around the orbit of her inner labia, when you get to the top move straight up a bit and you will be in the neighborhood. Probe there for a while and wait for her to react. Maybe all you'll be able to find is the firm area of her clitoral hood. When you do, concentrate on that with increased pressure and then you can speed up your flicking. If she gets excited, the clit itself may protrude enough to actually touch it with your tongue. If you can't find the opening at the front of the hood and wiggle the tip of your tongue in to touch it, don't worry, the pressure and motion on the outside will be enough for now (her clit may be too sensitive to withstand your direct touch).
Now kick off your training wheels and start experimenting. If she starts getting off, keep doing exactly whatever you're doing no matter how long it takes or how bad your neck, back and tongue hurts.
Until you get that far, leave the fingers out of it, because that may be distracting her. That should get you started.
Here is a primer by Bella. She doesn't come around much, but I'm sure she'd be happy someone is using her tips. I think she re-printed this from an internet article:
http://www.sexualforums.com/talk/showthread.php?t=4614
And don't read any of gentleman steve's posts on the subject because he's a dufus.

Seriously.