This page takes you to the committees formed in support of, and in opposition to, Proposition 8. From there you can follow the links to, for example, funders for Protectmarriage.com. (Note, be patient, pages are enormous and very slow to load).
Hundreds of thousands of dollars, if not millions, came from out-of-state--$200,000 from Galaxy Enterprises, of Alpine Utah, for example. $100,000 from Roger Byron of Salt Lake City, Utah. $100,000 from Josephine Templeton of Bryn Mawr, Pennsylvania. $100,000 from Michael Murray's Crystal Springs Foundation.