It is the same in fact. It depends where you are travelling. There is more aircraft companies who flight to Barcelona airport, it's the second airport of Spain.
It depends of your budget. There is a company who can drive you direct airport to the hotel. We advice you Novatel.
Novatel shuttles back and forth between Barcelona El prat ( Barcelona airport) and Toulouse Blagnac ( Toulouse airport). Please check website http://www.andorrabybus.com .It is very easy to book online or direct at the airport. For online booking, select your airport and terminal and after your hotel (Canillo Ski Plaza).
Some bus companies do not drive to Canillo and stop to Andorra La Vella. In this case, you should take another bus, public transport or a taxi. For public transport, check schedule and price, Here. For taxi, there is many taxi companies, Here.