There are numerous options for getting to La Paz, which include by plane, bus, ferry, or car.

If choosing to fly, there are two arrival airport options.  The first and most convenient is flying directly into the La Paz International Airport, which is located just outside town.  Flights from LAX (leaving and returning Thursdays and Sundays only) can be found with Aero Mexico.  Another option is to fly into the airport at San Jose del Cabo (SJD) the airport also serving the resorts of Cabo San Lucas.  This location deals with a larger number of carriers such as Alaska Airlines, American, America West, Mexicana and more.

To travel from SJD to La Paz by ground transportation, there are several options.  You can take a mini-bus service (EcoBaja Tours) directly from the SJD airport (Terminal 1) to the bus station at the center of La Paz near the waterfront for approximately $40 o/w (3 1/2 hours).  By standard bus (Aguila bus line, which also owns EcoBaja Tours), you need to go into the city of San Jose del Cabo; the taxi ride should cost around $6 USD.  From there, catching a bus to La Paz will cost around $6 USD.  Many buses leave every day, and the journey will take roughly four hours.  Another option from Cabo is to rent a car and drive to La Paz. 

From San Diego, California, on the border with Tijuana, it is quite convenient to take Volaris airlines (http://www.volaris.mx/en/) from the Tijuana airport (TIJ).  There is one flight at 11:05 am daily.  Volaris provides a shuttle from the San Diego airport or train station to TIJ for $20.

You can find good travel information for La Paz at this helpful web site, All About La Paz.  They also have a webcam where you can enjoy the bay of La Paz and see what the weather is like. 

If you are considering driving to La Paz from the U.S. visit this web site, All About Baja for a lot of helpful advice and tips. Driving to La Paz from southern California will take at least two days, since it's almost 1000 miles, so make sure to look at Driving in Mexico before choosing to get behind the wheel in Baja. 

The bus journey from Tijuana to La Paz will take more than 24 hours.  This option obviously takes a while, but it is a good way to see more of the country.

Visit Baja Ferries for information about getting to La Paz by sea.