Super Shuttle is a good option, and LAX (like SNA) has the Grayline
Disneyland Express.
Booking Disneyland Express ahead of time, online, will get you a couple bucks off.
And if you have an Entertainment Book, you have a coupon to get a couple bucks off Super Shuttle as well.
for the future, it's always very important to have the transportation costs in your head before deciding on an airport. For instance, we chose to fly into ONT airport once, b/c the airfare was better. I *thought* that super shuttle costs would be the same as from/to SNA. Ooh I was wrong! SS is something like $9 per person at SNA, but ONT was mega-bucks. Instead of a simple per person cost, it was x for the first person and much cheaper for the next 3 people. And hubby was flying separately from us, so we had TWO "first person" costs going each way. Not good. Didn't quite take over what we saved flying into ONT instead of SNA, but it was close.
So it's a good idea to get these costs figured out before choosing an airport.
In your case, since it's a huge price difference, and LAX isn't too different from SNA (I think super shuttle is 16 per person instead of SNA's 9-ish per person), you're OK, but for the future I hope my info is useful.
Also, for our last stay, we got a rate on a rental car, through hotwire, that was just about the same as 3 people taking Disneyland Express to and from LAX. And we only used something like 2 gallons of gas, maybe 3? So the gas costs weren't exorbitant. We had a hotel switch on our first day that would have required a taxi, so our costs were about the same renting the car vs DE+cab, and a bit easier since we could just keep DS's carseat installed in the car and not have to worry about doing that in a taxi.
If that's at all interesitng ot you, be sure to check out car rentals.
