Old West town in a Mailer novel (7)
I believe the answer is:
laramie
'old west town' is the definition.
The definition suggests a singular noun which matches the answer.
'a mailer novel' is the wordplay.
'novel' is an anagram indicator (letters in a new or novel order).
'a'+'mailer'='amailer'
'amailer' with letters rearranged gives 'LARAMIE'.
'in' is the link.
Can you help me to learn more?
(Other definitions for laramie that I've seen before include "US city" , "Town featuring in Westerns" , "Wyoming place" , "US town" , "Wyoming city" .)