Santa Barbara Municipal Airport: Take Santa Barbara MTD Route 11 into downtown rather than paying for a car for a 7-mile transfer. Allow roughly 25–35 minutes to lower State Street/Waterfront; a standard single ride is about $2.50. SBA is wonderfully convenient but can be expensive and has limited schedules.
Los Angeles International Airport: For a Santa Barbara-bound trip, the direct Santa Barbara Airbus is the sane option: roughly 2½–3½ hours depending on Los Angeles traffic, usually around $55–60 one way. The cheaper-looking FlyAway-to-Union Station-plus-Amtrak combination adds transfers and is only worth it if its timetable happens to line up perfectly. Build in serious buffer time: L.A. traffic is not theoretical.
Hollywood Burbank Airport: A useful alternative to LAX: Amtrak Pacific Surfliner trains stop at Burbank Airport on their way to Santa Barbara, about five times daily. Expect roughly 2½–3 hours and a fare in the $30-ish range, varying by train and date. It is often calmer than LAX, but do not assume a last-minute seat or perfect on-time running.
Santa Barbara Amtrak Station: This is the arrival point to choose from Los Angeles, San Diego, Ventura/Oxnard, San Luis Obispo and beyond: the Pacific Surfliner and Coast Starlight stop here. The station is beside the waterfront and an easy walk to lower State Street, the Funk Zone and many downtown hotels; take a short rideshare only if you are staying uptown, at the Mission or in Montecito. Coastal sections are beautiful, but the long-distance Coast Starlight is not a train to schedule tightly around.