im picking up my sister at LAX airport, how will the parking be at the arrivals section, toll or metered?

The parking structures in the Central Terminal Area are Pay on exit. It costs $3 for the first hour and then $2 every 20 minutes up to a maximum of $30/day.

However, I would suggest parking in the Cell Phone Waiting Lot right outside of the airport. Here you can park for free. Then when your sister arrives she can contact you when she is outside of the terminal and you can pull up at the curb to load without any cost.

You are not allowed to wait at the curb, that is you must be actively loading and you can not leave your car unattended. This is why you can wait until she calls you. They are very strict and violations could lead to tickets and/or having your car towed.

The link below tells you all about the parking.

If she does not have a way to contact you, then you will need to look at her flight arrival information. It will tell you the gate she arrives at. The first number in the gate is the Terminal. You can then park in the Central Terminal area at the structure corresponding to the correct terminal.

OC1999 nailed it. Go to the cell phone lot. OR, you can grab a burger at In N Out. I usually leave early enough to arrive an hour early. I get to In N Out, and BACK my car into a spot. One, because it's large, and two, because the drive thru line often winds through the lot and makes it difficult to back out. Then I chill out and watch the planes fly 100 feet over my head as they come in to land. Then I have my passenger light up their phone and call me the moment they land. I then walk inside, get in line, and get a double-double, etc. As soon as I get my order, I leave and drive the 200 yards south to the arrival level. By then, my passenger is usually ready. Once I had to make the loop again. But my arrival gets a double-double immediately upon arrival. Bonus!

you must look for info on their website because this week some of the airlines are changing terminals so traffic, parking, etc will all be affected