What are some of Joan Baez songs?

Not as far as I know- or at least, I don't believe she ever wrote songs specifically for Led Zeppelin. However, Led Zeppeling did cover material that she'd released (Babe I'm Gonna Leave You) but I...

Love is just a 4 letter word

My Generation and Pinball Wizard are a good place to start.

She sang "We Shall Overcome" solo and provided backup vocals for Dylan on "When the Ship Comes in" and for Len Chandler on "Eyes on the Prize."

1. Billie Jean2. Bulletproof3. Black n' Yellow4. Dynamite5. Break your heart6. California Gurls7. OMG8. Like a G69. Coming Home10. Blow11. Freak the Freak out12. Grenade13. Baby14. Never Say Never15....