I ran across a quite excellent 2007 BBC documentary on YouTube entitled Hotel California: LA from The Byrds to The Eagles.
Its basic premise is that the popular music scene in LA that began with The Byrds and Buffalo Springfield and culminated with the Eagles is a story of idealism corrupted by corporate commercialism. It is also a story--though less emphasized in this piece than it should be--about how the early promise of great groups such as CSNY was squandered when cocaine and speed replaced marijuana as the drug of choice.
The 90-minute documentary is divided into three sections. The first section focuses on the emergence of CSNY out of the ashes of The Byrds, Buffalo Springfield, and The Hollies as the first S. California super group. The second part--and the most interesting to me--is about the rise of the singer/song writer and merging of country, rock, and folk music with acts such as Jackson Browne, J.D. Souther, Carol King, James Taylor, Joni Mitchell, and Linda Ronstadt. Ronstadt, a personal favorite of mine, is an exception in this group as she was never a song writer. Her talent, as the documentary points out, was surrounding herself with great song writers and performing the best version of other people's songs.
The third part focuses on the Eagles as the most commercially successful group to arise from the crucible of the Troubador and the Laurel Canyon enclave of pop music talent.
If you are interested in the subject matter I strongly recommend this documentary.