Flying is also quite convenient and extremely time efficient. However, the flights are especially sensitive to weather can sometimes be delayed or cancelled due to wind or snow.
Toyama Airport is about 20 minutes away from Toyama station via bus (terminal (6), 400yen) and a 40 minute bus ride from Takaoka station bus terminal (1) (1100yen). You can take international flights to Beijing, Shanghai, Seoul and Taipei from the Toyama Airport. However, air fares are more expensive as compared to flying out from Narita Airport (Tokyo) or Kansai Airport (Osaka).
Komatsu Airport in Ishikawa prefecture is also a convenient airport. You can get there, most conveniently from either Kanazawa station or Komatsu station. Timetable and fare information can be found here.
ANA offers a really good deal from Toyama and Komatsu to Tokyo (Haneda) for around 10,000 yen if you book at least one month in advance. JAL offers a similar deal but only from Komatsu airport.
Central Japan International Airport in Nagoya has international airfares that cheaper if you depart from here as compared to departing from Toyama Airport