I'll at least point you in two direction. Vine on Vine in Hollywood at Fountain is a desert fondue place with a hip trendy martini crowd. New and pretty inexpensive.
Another place a real classic is on Ventura in Sherman Oaks, old fashioned popular and a little pricey. It's in Jonathan Gold's book but the phone number is wrong.
re: Colin Brown
Fondue French Restaurant in Sherman Oaks is located at 13359 Ventura Blvd., 818-501-0181, next door to the former JoeJoe's, which has just re-opened as Max, owned by Andre Guerrero, ex-chef at Linq. Fondue is old-fashioned, been there a long time, and is fairly popular on weekends.