San Jose International Airport
The San Jose International Airport is your best bet for flying into the area.
The free Airport Flyer bus #10 (http://www.vta.org/schedu...) at the airport connects to Santa Clara Transit Station, from which one can catch either VTA bus #22 (http://www.vta.org/schedu...) or Caltrain (http://www.caltrain.org) to Sunnyvale. The #22 bus line has many stops in Sunnvale along El Camino Real, from Lawrence Expressway in the east to Bernardo Avenue in the west. Caltrain stops in Sunnvale at both the Lawrence station as well as downtown Sunnyvale.
Taxi fare from San Jose Airport to Sunnyvale is approximately $27-30.
San Francisco International Airport
CalTrain's Sunnyvale station is next to old downtown, on Evelyn Avenue just West of Murphy Street.
Caltrain has a transfer point to BART via the Millbrae Station. BART goes to San Francisco International Airport.
Sunnyvale Caltrain Station
121 W. Evelyn Avenue, 1-800-660-4287. Caltrain connects San Jose with San Francisco, passing through Sunnyvale.See the websites (http://511.org/) or (http://tripplanner.transi...) for a bay area trip planner by public transit.