Getting to Val d'Isere is very easy. Chambery is the closest airport followed Grenoble, Geneva and Lyon. If you are looking to book your own transfers the most cost effective way of getting to resort is to book a shared transfers, alternatively you can take a private transfer or hire a car and drive to resort.
A few companies we recommend are:
Public coach:
Altibus - altibus.com/
Ben’s Bus - bensbus.co.uk/

Private minibus/car:
Europe transfer - europetransfer.com/
Cool bus - thecoolbus.co.uk/
ATS - a-t-s.net/