I take the Super Shuttle... super cheap, super easy
Really. I'm not a "shuttle" type person, but it REALLY is easy from LAX/SNA. Check out mousesavers.com for great info on shuttles and transportation at DL.
Try flying into a closer airport. Still nothing comparable to Magical Express, but easier access. John Wayne Airport is closer, as is, I think, Long Beach. Is this for a personal trip, or are we doing your work for you?
Grayline, however, runs a coach called Disneyland Resort Express.
You can also check the "sticky" info thread on the Disneyland Forum here, to find transportation threads and coupons for both Super Shuttle and the bus mentioned above.
Seriously, why not consider a car, I just returned from DL and was going to use a shuttle as we were staying within walking distance to DL. I was playing around with numbers and added a car on just for the heck of it and boy was I surprised, for 6 days it was cheaper to rent a car than to pay for Airfares and Hotel alone.
I ended up saving $200 just by adding on a car rental.