Actually there are normal public buses to KLIA, just like our
SBST and SMRT buses at Changi Airport. Sepang Omnibus have 2
services which connects KLIA with Nilai, Seremban and the various
little housing estates in between. The trip is long, the bus
condition is less than satisfactory, it is crowded and the bus
frequency is 30 mins. En route, the bus would stop at the Nilai Bus
Station which is just a stone's throw to the Nilai Railway Station,
where you can transfer to the KTM Komuter train to KL or
Seremban.