Thank you very much everybody, now I feel like an expert and I haven't ever been on those trains.

Yes abmj-jr, its airport to airport. Trying to fly into Guam on Star Alliance, which is served by NH ex-KIX only. Finding award flights from the USA to KIX is rough at times, so we were thinking of flying into NGO nonstop from SFO, then from NGO to KIX via train, etc. Finding award flights from KIX to SFO can also be a bruiser, so we're looking at ex-NGO on the return too so we'd need to find a way to get from KIX-NGO. If there was a cheapie $300-ish roundtrip flight from NGO or KIX to GUM on any carrier (Continental, JL, etc), we'd be happy to spend that too (use award miles for the SFO-Japan) as often times the KIX-GUM isn't readily available using UA miles.

Again, thank you everybody.