Los Angeles, CA to University of Phoenix-San Diego buses and trains from $25

Here are some trips other travelers have found on Routefriend.
$25
2h 55m
0 stops
GotoBus
$35
4h 49m
1 stop
Amtrak GotoBus
$37
2h 45m
0 stops
Amtrak
$48
4h 18m
1 stop
GotoBus Amtrak