FairVote - FairVote California is a project of FairVote.
Representation 2020 - Check out the Gender Parity Index and see how California ranks.
Ranked Choice Voting Resource Center - Provides a compilation of best practices and first-hand experiences from jurisdictions that have used this method of voting.

State and Local

Voter's Edge - What’s on your ballot?
Yes on Ranked Choice - Santa Cruz, CA based Rank Choice Voting group
Student Governments that use RCV/STV - There are 16 campuses in CA!
U.C. Santa Barbara - Open source program to run ranked choice voting elections

Other States