No fee required. I don't remember the directions to the drop off area for all parks which directions are a little bit different for each park. Ask the toll booth attendant, then thank him and drive on.
For Magic Kingdom, choose the second or third ltoll booth lane from the right side, and after going through the toll booth bear right at the big fork. Then left at the next allowable left that has a traffic light. The drop off area is a little ways down.