I believe the Metrolink goes all the way to San Clemente and you can bus it to Del Mar. At least that's what my Mom always tells me. And she/we use it to and from their house to mine in Corona. She lives near the Laguna Niguel station right there off the 5 near Crown Valley. I think there is one more stop and the end of the line for Metro after that in San Clemente. I'm sure Amtrak can get you there too.