You could go on Amtrak. It will cost you $70-80 per person each way and if you get lucky and don t have any delays the trip will be 12-16 hours. The nice thing about the train is that you have huge comfortable seats and you can walk around, but be warned that one leg of your trip will likely be by Amtrak bus. You could also take a Greyhound bus. It s slightly less expensive than Amtrak, but will definitely have more weird smelly people than the train and takes just as long. Just for comparison, Southwest Airlines is about twice as expensive but takes 1/10th the time.
Train or bus. Train is subject to delays on the railway and the bus is just full of sketchy people.
Bus or train. Bus is quicker and cheaper particularly if you buy your ticket in advance.
Amtrack. This gives you a chance to see the scenic side of California.
Train would be the best.....bluuh for the buses (I know a necessary evil...but thats a long bus ride...)