There are two airports convenient to Pasadena.
LAX offers a much better choice of airlines/originating cities/flights; also good fares are often easier to obtain using LAX. On the downside, lines for check-in and security can be very long at times. It will generally take about 30 minutes between LAX and Pasadena outside of rush hour, but up to an hour or even more at the busiest times.
Burbank is closer (20 minutes) and is generally much quicker to get through check-in and security than LAX, but is served by fewer airlines and most often requires connecting flights.
Ontario is another possibility: it's comparable to Burbank in terms of flights and hassle but about an hour away.
The best airfares these days are frequently to be found online, either at individual airline websites or from services such as Orbitz.
From the airport to the hotel there are basically two options:
Shuttle services Two companies, Prime Time Shuttle and SuperShuttle, serve LAX. There is a pickup stop in front of each terminal on the arrival level; just go out to the orange sign labeled "Shared Ride Vans" and tell the company representative stationed there where you want to go. Normally you'll get your ride within 15 minutes or so. It is possible to make an advance reservation online (http://www.primetimeshuttle.com/ or http://www.supershuttle.com/); that may get a better fare but will probably not affect how fast you get picked up. Typical one-way fares from LAX to Pasadena run about $20-30 per person. The same companies also serve Burbank and Ontario, with pickup outside baggage claim areas; the fares will be somewhat less and somewhat more, respectively.
Taxi: from LAX about $50 (or more if traffic is bad); from Burbank about $25.
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