There are many, many bootlegs of live shows, but only one that I know of that contains studio recordings. It's about 11 hours long with quite a wide range of st

There are many, many bootlegs of live shows, but only one that I know of that contains studio recordings. It's about 11 hours long with quite a wide range of stuff. There are recordings of them practicing Stairway to Heaven at several stages, including an early acoustic version, one of the first times they played together, and a couple demo versions with different solos. It's pretty cool to hear the song develop.