The schedules for the limousine bus are here:
https://www.limousinebus.co.jp/en/
The schedules for the Narita Express are here:
JR-EAST Train Reservation
The ticket counters for both are in the Arrivals area, so you can choose either one depending on when you emerge from Customs and Immigration. No reservations are needed.
Last edited by ksandness; Jun 7, 2019 at 7:33 am
Reason: better link