The five-day Brandywine Festival is due to take place at Weston Park in September.
The three books contain signatures from the author, which were cut out and pasted from letters.
Operator Nexus says the discovery at the base of an overhead line mast is "baffling".
The author used the desk during his tenure as Merton professor of English language and literature.
A well-known landmark thought to have links to JRR Tolkien's Lord of the Rings novels turns 90.
Volunteers clean and repair the gates designed by the great-nephew of JRR Tolkien in the 1990s.
Planning permission and listed building consent is granted to restore The Eagle and Child in Oxford.
Crews and actors were seen filming season three of the show at Portland Bill on Thursday.
