You'd better keep true to your word (you wouldn't be a liar now would you?)

The best way to get to Tochigi would be to fly to Narita Airport. From there, you'll probably need to take a train to Ueno station and you can change for a Tohoku-shinkansen Bullet Train that will take you quickly to Utsunomiya (the capital of Tochigi Prefecture). From Utsunomiya you catch a train, change at Oyama and get off at Sano station, which is the nearest station to where HLJ is.

I have no idea how near or far they are from the station, but I suppose you could try to walk or take a bus or taxi from Sano station to their location.

The next soonest flight you can catch as far as I can tell is on the 8th of February. One-way tickets (because after you get arrested for attempted murder I don't think you'll be flying back to Australia unless the Australian government decides to extradite you) prices range from $636 (Malaysia Airlines, Flight Centre Reference No. AUMH53420/17) to $1549 (Qantas, AUQF53839/6) Economy Class.

You can make an online flight booking here or call 133 133.

Let us know how this all pans out.

P.S.: if you don't want to double-back from Utsunomiya to Oyama, you might be able to take a train from Ueno to Oyama, but it'd be a slower regular train as opposed to a bullet train - but the route would be more direct and the ticket would be cheaper too.