Cabazon is the other outlet B-Line was referring to. it's right next to the Morongo Hotel and Casino, so if you get tired of shopping and your wife is still going, you can hop in and do a little gambling.

there's the Citadel off the 10 freeway, but I'm not sure how good it is.

for shopping centers/areas in LA, you can check out Westfield Century City, Beverly Center, Third Street Promenade in Santa Monica, The Grove, the Rodeo Drive area in Beverly Hills if you want some REALLY expensive stuff.

EDIT: forgot to also mention South Coast Plaza in Costa Mesa down in Orange County. about 45 minutes away from LA.