Getting to tokyo from narita after 9pm

Hi,

Our flight is scheduled to arrive at narita at 20:35 and as i saw, last express train to tokyo is at 21:46. It is our first time in japan.
Is it adviseable to pre-order tickets for last train or consider getting by bus?

If yr flight arr on time you can take that last EXP.
Dep 21:46(T2,w/T3) is NOT "last", that is JR-East's EXP "N'EX".
http://www.jreast.co.jp/e/nex/index.html?src=gnavi
You can take Keisei Railways EXP "SkyLiner" for Keisei-Ueno.
http://www.keisei.co.jp/keisei/tetudou/skyliner/us/ae_outline/index.ph...
http://www.keisei.co.jp/keisei/tetudou/skyliner/us/ae_timetable/index....
http://i.imgur.com/pHxFMW5.png

If would like to go to JR Tokyo stn, get off at Keisei-Nippori,
then take JR Yamanote(Outer Track) or KeihinTohoku line fr Nippori(JR) stn via transfering ticket gate .
http://www.jreast.co.jp/e/stations/e1184.html
JR Yamanote and KeihinTohoku line is regular commuter train no reserved seat car.

Bus is cheper than EXP.

Thank you