Eldorado Park in Long Beach has (or had) a very nice archery range. There appears to be a club that uses the facilities and could probably offer more information here is their info:
EL DORADO ARCHERS (NAA)
El Dorado Park
Spring St/605 Freeway
Long Beach, CA
FREE ARCHERY INSTRUCTION
Saturday Classes * Age 8-18 * Adults welcome
For more information, call:
Aletha Donathan, Head Archery Instructor
714-895-0193(w)
562-924-8880(h)
THIS (click here) website has a list of southern california archery clubs and ranges