As I mentioned to someone else, you might check out Rogers Gardens over in Newport to see who they would recommend:
http://rogersgardens.com/
Another option is to search for Landscape Contractors nearby on Houzz...
If you are interested in the hardscape end of the yard, Go Pavers can help:
http://www.gopavers.com/
And, if you are over in the Newport Beach area, a trip to Rogers Gardens might yield recommendations on local landscape contractors that they recommend:
http://rogersgardens.com/
Enjoy designing!