Parent Organization:
California Native Plant Society

Other Organizations:
Palos Verdes Peninsula Land Conservancy
Southern California Botanists

Books and Articles on Growing Native Plants:
Building a Healthy Garden with California Native Plants - includes list of books on plants, plant selection and culture, integrated pest management and organizations.
"California Native Plants in Your Garden," article by Tony Baker
List of Books on Growing Native Plants from the PVPLC

Botanic Gardens:
Rancho Santa Ana Botanic Garden
Santa Barbara Botanic Garden

Classes:
Rancho Santa Ana Botanic Garden. Classes and events
UC Riverside Extension. Field and nature study
University and Jepson Herbaria. Educational Programs and Activities

Hikes, Walks and Tours:
Angeles Chapter, Sierra Club, Natural Science Section
George F Canyon
Madrona Marsh
Palos Verdes Peninsula Land Conservancy

Native Plant Nurseries:
Las Pilitas Nurseries
Native Plant Sources
Native Sons
Natural Landscapes, Portuguese Bend
Theodore Payne Foundation

Reference (photos and other information about native plants):
CalFlora   Online services suspended Feb. 1, 2003 due to funding shortfall.
California Wildflowers Bibliography
Wildflowers of Southern California - a Photographic Gallery
Southern California Wildflowers and Other Plants (has a large number of very useful links)

Wildflower Viewing in Southern California:
Wildflowers on BLM Lands in California
Desert Wildflower Watch
Mojave Desert Spring Wildflowers
Suggested Wildflower Viewing Areas