who are the owners os of record of 65680 avenida ladera, desert hot
springs, ca 92240

Just go to the assessor/recorder's office - or have someone do so.  In
Cal. the ownership of property is no secret, but since you don't have
the name of the owner you will probably have to have the parcel
number, but maybe the street address will do.  Any realtor should have
a parcel map.
On  the site for another Ca. county, it was stated that state law
prohibited putting recorded documents online, but Riverside Cy. seems
to provide just this service, only with a disclaimer for accuracy, but
I personally do not know if it possible to find ownership from a
document that could be accessed online.