I like Rick Suchow's site for the bass-related memorabilia and interesting info. It also includes some isolation clips of McCartney from the Sgt Pepper era. What's better are the significant number of Jamerson clips (isolating bass). Unfortunately, these require a password (which Rick says he'll Email). I listened to them all before they became restricted (to avoid a copyright issue) and found them very interesting. Kudos to the folks who make this kind of stuff available to the rest of us.