Placer Title posted a brochure of where are the best lights. One of my two favorites are the lights on Pebble Creek Drive in Rocklin (which is what I think you're referring to by the BelAir...) and the Dovewood Court in Orangevale have been a tradition to view for many years.
I also was fortunate enough to view the Downtown Theatre of Lights show at Front Street and K last week. It's FREE (free parking on the streets, and free show), hosted by the downtown merchants. There is a show at 6:15 and 7:45 every night up to Christmas. It's about 15-20 minutes long and a very fun reason to go downtown, have some dinner and enjoy the restaurants and shops downtown.
If someone wants me to email them the list of light displays, just email me. if I was smart enough I'd know how to stick it here in a link,...but I'm not.