Nordstrom Rack at Mission Valley: Good selection of small sized shoes in sizes 4-5. I also see size 23 jeans here every now and then.

Banana Republic Factory Store at the Carlsbad Premium Outlets: The factory store carries petite sizes down to petite 00 and petite xxs. The xxsp actually runs pretty small, and I've had some good luck there. Head over especially on holiday three day weekends...the discounts are amazing.

Theory outlet at the Carlsbad Premium Outlets: Theory size 00 items at a great discount. Just as with the BR outlet, visit on holiday weekends for the best discounts.

Ann Taylor Outlet at the Las Americas Premium Outlets: Carries petite sizes down to size XXSP and 00P. Great deals can be had during holiday three-day weekends.

Ann Taylor at University Town Center (UTC): As of the date of this post, the only Ann Taylor in San Diego that carries sizes XXSP and 00P in store.