Need help getting to LA By Train from San marcos and back again

Question

I helping someone out who lived up in LA doesn't know that much about san diego..

Thank you

Answer 1

from either Solona beach you can take amtrak directy to Los Angeles

from oceanside you can take either Metrolink or amtrak from there to Los Angeles

Answer 2

You friend needs to take the Pacific Surfliner and get off at the Oceanside station.    Schedules are here:  

http://www.amtrak.com/servlet/ContentSer...

It's about a 2 hour trip each way.  San Marcos is about 10 - 15 minutes inland from Oceanside on the 78 freeway.