Descriptions of the Archbishops' official papers are available on the Library's online catalogue of archives and manuscripts (available through ‘search collections', left). They do not survive in great quantity prior to the mid 19th century, and a thirty year closure rule applies.
E-mail: firstname.lastname@example.org 
Please use the subject line: Archbishops' Papers Enquiry
Tel: +44 (0)20 7898 1400
Post: Archbishops' Papers Enquiry, Lambeth Palace Library, London, SE1 7JU, UK.