Well if you live in So Cal like me you're in luck. The flight is a little over an hour down to La Paz. The flights are cheap from aerocalifornia or aeromexico. The prices are about
$250 RT, but you may find a package deal that is cheaper.
Cabs are plentiful in La Paz, and the bus is an option for those who are stretching pesos. But let's face it, your own wheels is the ultimate in freedom. You can follow your nose, not know quite where you are going, and see whatever you want.
When you fill up, it's at Pemex or nothing. There is no self-serve. You say "para llegar", the local equivalent to "fill 'er up".
We took Aero California on a DC-9 (!!) from Los Angeles to Loreto and back from La Paz. Can't say a whole lot good about them because they failed to get one of our bags on the plane from LA. Since we were kayaking one-way from Loreto to La Paz, my kayaking partner had to do without all of his clothes for the entire trip. Aero California has no compensation policy for lost baggage. Thanks to the Baja Expeditions office, the bag was forwarded to La Paz and we were able to pick it up there.
I can't say anything good about Aero California's closest competitor either, which is Aero Mexico. We met another traveler in Loreto who said Aero Mexico had lost her bag 3 days earlier and had no idea where it was! There were 3 or 4 other people on our flight who didn't get their bags. I suspect a conspiracy between the airline and the local shops: all of the shops in Loreto had socks, underwear and tooth brushes prominently displayed!
We took taxi vans to & from the airports and also to our first beach from Loreto to meet our boat. I would recommend using a VERY reliable car in Baja. We saw a couple of people on the side of the road stranded in the middle of nowhere in the desert. Not fun!!!
Of course, we used our kayaks, panga and the Rio Rita to get around for most of the trip.
From Tijuana to Los Cabos: Three major bus companies, Autotransportes de Baja California (ABC), Transportes Aquila and Tres Estrelles de Oro provide efficient service on the peninsula with modern, clean, fast buses.