Flight
This airport is closest to my parents home and seems to be the least expensive option for Southwest flights from smaller cities. It's very easy to get in and out of as it is a smaller airport.
Flight
This airport is closer to the venue, but is busier. You may find SD has better priced flights if you are coming from a larger city. It is also a much busier airport, anticipate traffic.
House Or Rental
There are tons of gorgeous places to stay in Temecula near the venue and you'll be about 30 min from San Diego if you want to extend your stay after the wedding.
Hotel