Letter among 350 items of rock memorabilia sold at Boston auction
Joan Osborne, Marshall Crenshaw and Ben E. King will also perform at 34th annual charity concert
Eight studio albums and three compilations from Beatles icon can be streamed from today
The guitar was given as a gift to Lennon's cousin David Birch in 1967
A transcript from Chapman's recent parole hearing has been released
Chapman refused release for the eighth time
1970s letter was angry at Keith Moon and Harry Nilsson for urinating on studio console
The correspondence, titled 'A Matter Of Pee', goes under the hammer tomorrow
Lennon brought Kenwood in 1964
The Beatles legend's detention sheets are up for sale