Here are some suggestions for airports and hotels. John Wayne is the closest airport (~30 min). San Diego and LAX are each ~ 1 hour drive from San Clemente. For lodging, Airbnb or VRBO also have many options available!
Hotel
Casablanca Inn
1601 North El Camino Real, San Clemente, CA 92672
Flight
John Wayne Airport, Orange County
The closest airport
Flight
San Diego International Airport
Flight
LAX
Hotel
Holiday Inn Express San Clemente N – Beach Area, an IHG Hotel